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Q. What's the difference between a research article and a review article?

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Answered By: Sarah Naomi Campbell Last Updated: Sep 07, 2018     Views: 214726

Watch this short video to learn about types of scholarly articles, including research articles and literature reviews!

Not in the mood for a video? Read on!

What's the difference between a research article and a review article?

Research articles , sometimes referred to as empirical  or primary sources , report on original research. They will typically include sections such as an introduction, methods, results, and discussion.

Here is a more detailed explanation of research articles .

Review articles , sometimes called literature reviews  or secondary sources , synthesize or analyze research already conducted in primary sources. They generally summarize the current state of research on a given topic.

Here is a more detailed explanation of review articles .

The video above was created by the Virginia Commonwealth University Libraries .

The defintions, and the linked detailed explanations, are paraphrased from the Publication Manual of the American Psychological Association , 6th ed .

The linked explanations are provided by the Mohawk Valley Community College Libraries .

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NFS 4021 Contemporary Topics in Nutrition: Research Articles vs Review Articles

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Research Articles and Review Articles Defined Review

"A  research article  is a  primary source ...that is, it  reports the methods and results of an original study performed by the authors . The kind of study may vary (it could have been an experiment, survey, interview, etc.), but in all cases, raw data have been collected and analyzed by the authors, and conclusions drawn from the results of that analysis.

A  review article  is a  secondary source ...it is written about other articles, and does not report original research of its own.  Review articles are very important, as they draw upon the articles that they review to suggest new research directions, to strengthen support for existing theories and/or identify patterns among existing research studies.   For student researchers, review articles provide a great overview of the existing literature on a topic.    If you find a literature review that fits your topic, take a look at its references/works cited list for leads on other relevant articles and books!"

From  https://apus.libanswers.com/faq/2324 , "What's the difference between a research and a review article?"

  • Example of a RESEARCH Article Lin CL, Huang LC, Chang YT, Chen RY, Yang SH. Effectiveness of Health Coaching in Diabetes Control and Lifestyle Improvement: A Randomized-Controlled Trial. Nutrients. 2021 Oct 29;13(11):3878.
  • Example of a REVIEW Article Ojo O, Ojo OO, Adebowale F, Wang XH. The Effect of Dietary Glycaemic Index on Glycaemia in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. 2018 Mar 19;10(3):373.

Difference between Reviews and Research Articles

Review Article: Identifies previously published research on a topic and summarizes the information (secondary source). Discusses what is already known and can be used to identify gaps in the field.  Usually no set layout. No original research is being presented. Written for a more general audience and easier to read. Both Written by a subject expert such as a scientist or researcher. Can be published in a scholarly, peer-reviewed journal. Research Article: Follows the scientific method. Usually provides a brief background on prior research (introduction) Conducts an experiment and reports the findings. Authors have NEW original research data (primary source) and discusses their results. Written at an advanced level; usually contains lots of jargon.

Research Article Break Down Review

Research articles follow a particular format.  Look for:

  • A brief  introduction  will often include a review of the existing literature on the topic studied, and explain the rationale of the author's study.
  • A  methods  section, where authors describe how they collected and analyzed data.  Statistical analysis are included.  
  • A  results  section describes the outcomes of the data analysis.  Charts and graphs illustrating the results are typically included.
  • In the  discussion , authors will explain their interpretation of their results and theorize on their importance to existing and future research.
  • References  or  works cited  are always included.  These are the articles and books that the authors drew upon to plan their study and to support their discussion.
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Review vs. Research Articles

How can you tell if you are looking at a research paper, review paper or a systematic review  examples and article characteristics are provided below to help you figure it out., research papers.

A research article describes a study that was performed by the article’s author(s). It explains the methodology of the study, such as how data was collected and analyzed, and clarifies what the results mean. Each step of the study is reported in detail so that other researchers can repeat the experiment.

To determine if a paper is a research article, examine its wording. Research articles describe actions taken by the researcher(s) during the experimental process. Look for statements like “we tested,” “I measured,” or “we investigated.” Research articles also describe the outcomes of studies. Check for phrases like “the study found” or “the results indicate.” Next, look closely at the formatting of the article. Research papers are divided into sections that occur in a particular order: abstract, introduction, methods, results, discussion, and references.

Let's take a closer look at this research paper by Bacon et al. published in the International Journal of Hypertension :


Review Papers

Review articles do not describe original research conducted by the author(s). Instead, they give an overview of a specific subject by examining previously published studies on the topic. The author searches for and selects studies on the subject and then tries to make sense of their findings. In particular, review articles look at whether the outcomes of the chosen studies are similar, and if they are not, attempt to explain the conflicting results. By interpreting the findings of previous studies, review articles are able to present the current knowledge and understanding of a specific topic.

Since review articles summarize the research on a particular topic, students should read them for background information before consulting detailed, technical research articles. Furthermore, review articles are a useful starting point for a research project because their reference lists can be used to find additional articles on the subject.

Let's take a closer look at this review paper by Bacon et al. published in Sports Medicine :


Systematic Review Papers

A systematic review is a type of review article that tries to limit the occurrence of bias. Traditional, non-systematic reviews can be biased because they do not include all of the available papers on the review’s topic; only certain studies are discussed by the author. No formal process is used to decide which articles to include in the review. Consequently, unpublished articles, older papers, works in foreign languages, manuscripts published in small journals, and studies that conflict with the author’s beliefs can be overlooked or excluded. Since traditional reviews do not have to explain the techniques used to select the studies, it can be difficult to determine if the author’s bias affected the review’s findings.

Systematic reviews were developed to address the problem of bias. Unlike traditional reviews, which cover a broad topic, systematic reviews focus on a single question, such as if a particular intervention successfully treats a medical condition. Systematic reviews then track down all of the available studies that address the question, choose some to include in the review, and critique them using predetermined criteria. The studies are found, selected, and evaluated using a formal, scientific methodology in order to minimize the effect of the author’s bias. The methodology is clearly explained in the systematic review so that readers can form opinions about the quality of the review.

Let's take a closer look this systematic review paper by Vigano et al. published in Lancet Oncology :


Finding Review and Research Papers in PubMed

Many databases have special features that allow the searcher to restrict results to articles that match specific criteria. In other words, only articles of a certain type will be displayed in the search results. These “limiters” can be useful when searching for research or review articles. PubMed has a limiter for article type, which is located on the left sidebar of the search results page. This limiter can filter the search results to show only review articles.

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Review Article vs Research Article

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Review Article vs Research Article

Review articles and Research Articles are two different types of scholarly publications that serve distinct purposes in the academic literature.

Research Articles

A Research Article is a primary source that presents original research findings based on a specific research question or hypothesis. These articles typically follow a standard format that includes an introduction, literature review, methodology, results, discussion, and conclusion sections. Research articles often include detailed descriptions of the research design, data collection and analysis procedures, and the results of statistical tests. These articles are typically peer-reviewed to ensure that they meet rigorous scientific standards before publication.

Review Articles

A Review Article is a secondary source that summarizes and analyzes existing research on a particular topic or research question. These articles provide an overview of the current state of knowledge on a particular topic, including a critical analysis of the strengths and limitations of previous research. Review articles often include a meta-analysis of the existing literature, which involves combining and analyzing data from multiple studies to draw more general conclusions about the research question or topic. Review articles are also typically peer-reviewed to ensure that they are comprehensive, accurate, and up-to-date.

Difference Between Review Article and Research Article

Here are some key differences between review articles and research articles:

In summary, research articles and review articles serve different purposes in the academic literature. Research articles present original research findings based on a specific research question or hypothesis, while review articles summarize and analyze existing research on a particular topic or research question. Both types of articles are typically peer-reviewed to ensure that they meet high standards of scientific rigor and accuracy.

Also see Research Methods

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Academia Insider

What Is The Difference Between A Scholarly Research Article And A Review Article?

If you are new in the academic world, you may find the types of academic articles dizziying. The more common ones include research articles, and also review articles. How are they similar and different from each other? Distinguishing between research and review articles is crucial. 

In this post, let’s explore what research and review articles are, and how are they different.

Research Article vs. Review Article

What is a research article .

A research article serves as the cornerstone of the academic and scientific community, standing as a detailed report on original findings.

Unlike review articles which synthesise existing literature to provide an overview, research articles present primary research with fresh data, exploring uncharted territories within a specific field.

review article and research article difference

The devil is in the details when it comes to these scholarly works. Original studies not only pose a research question but delve into methodologies that range from complex experimental designs to detailed observations.

Scholarly articles are often peer-reviewed, meaning that other experts in the field scrutinise the work before publication to ensure its validity and contribution to the field.

The empirical nature of research articles means that the raw data and analysis methods are laid bare for replication—a fundamental tenet of scientific inquiry. These papers typically include:

  • Introduction: Introduces the problem
  • Methodology: T he means by which the study was conducted
  • Results: F indings from the study
  • Discussion: Connects the findings to the bigger picture, highlighting implications and potential for future research.

While some journals accept such articles readily, the journey of a paper from research question to published research is fraught with meticulous data collection and rigorous peer evaluation.

For the keen observer, it’s the systematic reviews and meta-analyses that truly offer a glimpse into the current state of understanding, weaving through the tapestry of existing knowledge to pinpoint gaps and suggest paths forward.

It’s this level of detail—often hidden in plain sight in methods and results—that serves as a rich vein of information for those looking to conduct systematic reviews or embark on a similar empirical journey.

Whether it’s a clinical case study or a large-scale trial, the research article is an essential treasure in the scholarly literature, serving as a building block for academic writing and future exploration.

What Is A Review Article?

A review article stands out in the scholarly world as a synthesis of existing research, providing a critical and comprehensive analysis of a particular topic.

Unlike original research articles that report new empirical findings, review articles serve as a bridge connecting a myriad of studies, offering an overview that discerns patterns, strengths, and gaps within published work.

review article and research article difference

Peer-reviewed and systematically organised, these articles are essential for scholars who wish to familiarise themselves with the current state of knowledge on a given subject without having to delve into each individual research paper.

Insiders know that the crafting of a review article is an art in itself. Authors meticulously collect and analyse data from various sources, often employing methods like meta-analysis or systematic review searches to compare and combine findings.

They don’t just summarise existing literature; they synthesise it, providing new insights or revealing unexplored areas that could benefit from future research. It’s a rigorous process, often involving the intricate task of:

  • Comparing clinical trials,
  • Conducting extensive literature reviews, or even
  • Generating new frameworks for understanding complex academic concepts.

The value of a well-conducted review is immense. Journals publishing these articles often see them as keystones, providing a foundation upon which other researchers can build.

Such reviews can point to the need for new primary research, challenge existing paradigms, or even sometimes shift the direction of scholarly inquiry.

For the discerning academic, a review article is not just a summary—it’s a roadmap for what comes next in the quest for knowledge.

How Are Review And Research Articles Different?

In the scholarly cosmos, the distinction between a research article and a review article is fundamental, yet it’s a source of perplexity for budding academics. Diving into the anatomy of these articles reveals their distinct roles in academia.

Original Research vs Synthesised Knowledge

A research article is an original study, presenting novel findings. It follows a stringent structure: an abstract to summarize the study, an introduction to set the stage, followed by methods, results, and a discussion that connects the findings to broader implications.

A review article instead synthesises the information from one or many of these original studies, into an article to allow easier reading. Some also offer additional insights for the readers. 

Anatomy & Structure

An original research article is usually brimming with original data, charts, and perhaps phrases like “we investigated” or “the study found,” signifying fresh empirical insights. At the most basic, a research article usually contains sections such as:

  • Introduction
  • Methodology
  • Future research ideas

A review article usually begins with an abstract summarising the scope and findings of the review. The main body is divided into sections that often include:

  • An introduction to the topic
  • A discussion segment that synthesises and analyses the compiled research
  • Subtopics that further categorise the research by themes or methodologies. 

Finally, it concludes with a summary or conclusion that reflects on the current state of research, identifies gaps, and may suggest directions for future studies, accompanied by a thorough list of references.

A research article is written to share new findings and original data on a particular research. This means the information are fresh, and new to the scientific community.

An example title of a research article may be “Investigating Necrotic Enteritis in 15 Californian Broiler Chicken Farms.”

A review article is more akin to an academic digest, offering a synthesis of existing research on a topic. It typically lacks the methodology and results sections found in research papers.

The main goal is to give a panoramic view of the existing literature, gaps, and sometimes, a meta-analysis combining findings from various studies to distill a more substantial conclusion.

An example of a review article about Necrotic Enteritis may be something like this: “Necrotic Enteritis in Broiler Chickens – What We Know So Far.” 

Impact and Use in Academia

Research articles are the primary sources, documenting original work from scientists, as they conduct researches in their fields.

review article and research article difference

Original research articles are crucial in academia as they contribute new knowledge, support evidence-based advancements, and form the foundation for subsequent scholarly inquiry.

Research articles: 

  • Provide detailed methodology and results for peer scrutiny
  • Foster academic dialogue,
  • Often the preferred source for cutting-edge information in a given field, and
  • Directly impacting teaching, policy-making, and further research.
Review articles are summaries that distill wisdom from multiple sources to shed light on the current state of knowledge, often guiding future research.

They are usually seen as secondary sources, containing insights that research articles might not individually convey.

Journals prize them for their ability to provide a systematic overview, and while they may not require the substantial funding necessary for conducting original research, their scholarly impact is substantial.

Wrapping Up

In the academic landscape, research articles and review articles form the backbone of knowledge dissemination and scholarly progress.

Research articles introduce novel insights, pushing the boundaries of understanding, while review articles offer a synthesis of existing findings, guiding future studies.

Both are essential: one for its fresh empirical contributions, the other for its comprehensive overviews and analytical prowess.

Together, they underpin the scientific method, spur academic debate, and serve as the keystones of educational advancement and informed decision-making in the quest for enlightenment and innovation.

review article and research article difference

Dr Andrew Stapleton has a Masters and PhD in Chemistry from the UK and Australia. He has many years of research experience and has worked as a Postdoctoral Fellow and Associate at a number of Universities. Although having secured funding for his own research, he left academia to help others with his YouTube channel all about the inner workings of academia and how to make it work for you.

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Scholarly Journals and Popular Magazines: Differences in Research, Review, and Opinion Articles

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Research Articles, Reviews, and Opinion Pieces

Scholarly or research articles are written for experts in their fields. They are often peer-reviewed or reviewed by other experts in the field prior to publication. They often have terminology or jargon that is field specific. They are generally lengthy articles. Social science and science scholarly articles have similar structures as do arts and humanities scholarly articles. Not all items in a scholarly journal are peer reviewed. For example, an editorial opinion items can be published in a scholarly journal but the article itself is not scholarly. Scholarly journals may include book reviews or other content that have not been peer reviewed.

Empirical Study: (Original or Primary) based on observation, experimentation, or study. Clinical trials, clinical case studies, and most meta-analyses are empirical studies.

Review Article: (Secondary Sources) Article that summarizes the research in a particular subject, area, or topic. They often include a summary, an literature reviews, systematic reviews, and meta-analyses.

Clinical case study (Primary or Original sources): These articles provide real cases from medical or clinical practice. They often include symptoms and diagnosis.

Clinical trials ( Health Research): Th ese articles are often based on large groups of people. They often include methods and control studies. They tend to be lengthy articles.

Opinion Piece:  An opinion piece often includes personal thoughts, beliefs, or feelings or a judgement or conclusion based on facts. The goal may be to persuade or influence the reader that their position on this topic is the best.

Book review: Recent review of books in the field. They may be several pages but tend to be fairly short. 

Social Science and Science Research Articles

The majority of social science and physical science articles include

  • Journal Title and Author
  • Abstract 
  • Introduction with a hypothesis or thesis
  • Literature Review
  • Methods/Methodology
  • Results/Findings

Arts and Humanities Research Articles

In the Arts and Humanities, scholarly articles tend to be less formatted than in the social sciences and sciences. In the humanities, scholars are not conducting the same kinds of research experiments, but they are still using evidence to draw logical conclusions.  Common sections of these articles include:

  • an Introduction
  • Discussion/Conclusion
  • works cited/References/Bibliography

Research versus Review Articles

  • 6 Article types that journals publish: A guide for early career researchers
  • INFOGRAPHIC: 5 Differences between a research paper and a review paper
  • Michigan State University. Empirical vs Review Articles
  • UC Merced Library. Empirical & Review Articles
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Writing a Scientific Review Article: Comprehensive Insights for Beginners

Ayodeji amobonye.

1 Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, P.O. Box 1334, KwaZulu-Natal, Durban 4000, South Africa

2 Writing Centre, Durban University of Technology, P.O. Box 1334 KwaZulu-Natal, Durban 4000, South Africa

Japareng Lalung

3 School of Industrial Technology, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia

Santhosh Pillai

Associated data.

The data and materials that support the findings of this study are available from the corresponding author upon reasonable request.

Review articles present comprehensive overview of relevant literature on specific themes and synthesise the studies related to these themes, with the aim of strengthening the foundation of knowledge and facilitating theory development. The significance of review articles in science is immeasurable as both students and researchers rely on these articles as the starting point for their research. Interestingly, many postgraduate students are expected to write review articles for journal publications as a way of demonstrating their ability to contribute to new knowledge in their respective fields. However, there is no comprehensive instructional framework to guide them on how to analyse and synthesise the literature in their niches into publishable review articles. The dearth of ample guidance or explicit training results in students having to learn all by themselves, usually by trial and error, which often leads to high rejection rates from publishing houses. Therefore, this article seeks to identify these challenges from a beginner's perspective and strives to plug the identified gaps and discrepancies. Thus, the purpose of this paper is to serve as a systematic guide for emerging scientists and to summarise the most important information on how to write and structure a publishable review article.

1. Introduction

Early scientists, spanning from the Ancient Egyptian civilization to the Scientific Revolution of the 16 th /17 th century, based their research on intuitions, personal observations, and personal insights. Thus, less time was spent on background reading as there was not much literature to refer to. This is well illustrated in the case of Sir Isaac Newton's apple tree and the theory of gravity, as well as Gregor Mendel's pea plants and the theory of inheritance. However, with the astronomical expansion in scientific knowledge and the emergence of the information age in the last century, new ideas are now being built on previously published works, thus the periodic need to appraise the huge amount of already published literature [ 1 ]. According to Birkle et al. [ 2 ], the Web of Science—an authoritative database of research publications and citations—covered more than 80 million scholarly materials. Hence, a critical review of prior and relevant literature is indispensable for any research endeavour as it provides the necessary framework needed for synthesising new knowledge and for highlighting new insights and perspectives [ 3 ].

Review papers are generally considered secondary research publications that sum up already existing works on a particular research topic or question and relate them to the current status of the topic. This makes review articles distinctly different from scientific research papers. While the primary aim of the latter is to develop new arguments by reporting original research, the former is focused on summarising and synthesising previous ideas, studies, and arguments, without adding new experimental contributions. Review articles basically describe the content and quality of knowledge that are currently available, with a special focus on the significance of the previous works. To this end, a review article cannot simply reiterate a subject matter, but it must contribute to the field of knowledge by synthesising available materials and offering a scholarly critique of theory [ 4 ]. Typically, these articles critically analyse both quantitative and qualitative studies by scrutinising experimental results, the discussion of the experimental data, and in some instances, previous review articles to propose new working theories. Thus, a review article is more than a mere exhaustive compilation of all that has been published on a topic; it must be a balanced, informative, perspective, and unbiased compendium of previous studies which may also include contrasting findings, inconsistencies, and conventional and current views on the subject [ 5 ].

Hence, the essence of a review article is measured by what is achieved, what is discovered, and how information is communicated to the reader [ 6 ]. According to Steward [ 7 ], a good literature review should be analytical, critical, comprehensive, selective, relevant, synthetic, and fully referenced. On the other hand, a review article is considered to be inadequate if it is lacking in focus or outcome, overgeneralised, opinionated, unbalanced, and uncritical [ 7 ]. Most review papers fail to meet these standards and thus can be viewed as mere summaries of previous works in a particular field of study. In one of the few studies that assessed the quality of review articles, none of the 50 papers that were analysed met the predefined criteria for a good review [ 8 ]. However, beginners must also realise that there is no bad writing in the true sense; there is only writing in evolution and under refinement. Literally, every piece of writing can be improved upon, right from the first draft until the final published manuscript. Hence, a paper can only be referred to as bad and unfixable when the author is not open to corrections or when the writer gives up on it.

According to Peat et al. [ 9 ], “everything is easy when you know how,” a maxim which applies to scientific writing in general and review writing in particular. In this regard, the authors emphasized that the writer should be open to learning and should also follow established rules instead of following a blind trial-and-error approach. In contrast to the popular belief that review articles should only be written by experienced scientists and researchers, recent trends have shown that many early-career scientists, especially postgraduate students, are currently expected to write review articles during the course of their studies. However, these scholars have little or no access to formal training on how to analyse and synthesise the research literature in their respective fields [ 10 ]. Consequently, students seeking guidance on how to write or improve their literature reviews are less likely to find published works on the subject, particularly in the science fields. Although various publications have dealt with the challenges of searching for literature, or writing literature reviews for dissertation/thesis purposes, there is little or no information on how to write a comprehensive review article for publication. In addition to the paucity of published information to guide the potential author, the lack of understanding of what constitutes a review paper compounds their challenges. Thus, the purpose of this paper is to serve as a guide for writing review papers for journal publishing. This work draws on the experience of the authors to assist early-career scientists/researchers in the “hard skill” of authoring review articles. Even though there is no single path to writing scientifically, or to writing reviews in particular, this paper attempts to simplify the process by looking at this subject from a beginner's perspective. Hence, this paper highlights the differences between the types of review articles in the sciences while also explaining the needs and purpose of writing review articles. Furthermore, it presents details on how to search for the literature as well as how to structure the manuscript to produce logical and coherent outputs. It is hoped that this work will ease prospective scientific writers into the challenging but rewarding art of writing review articles.

2. Benefits of Review Articles to the Author

Analysing literature gives an overview of the “WHs”: WHat has been reported in a particular field or topic, WHo the key writers are, WHat are the prevailing theories and hypotheses, WHat questions are being asked (and answered), and WHat methods and methodologies are appropriate and useful [ 11 ]. For new or aspiring researchers in a particular field, it can be quite challenging to get a comprehensive overview of their respective fields, especially the historical trends and what has been studied previously. As such, the importance of review articles to knowledge appraisal and contribution cannot be overemphasised, which is reflected in the constant demand for such articles in the research community. However, it is also important for the author, especially the first-time author, to recognise the importance of his/her investing time and effort into writing a quality review article.

Generally, literature reviews are undertaken for many reasons, mainly for publication and for dissertation purposes. The major purpose of literature reviews is to provide direction and information for the improvement of scientific knowledge. They also form a significant component in the research process and in academic assessment [ 12 ]. There may be, however, a thin line between a dissertation literature review and a published review article, given that with some modifications, a literature review can be transformed into a legitimate and publishable scholarly document. According to Gülpınar and Güçlü [ 6 ], the basic motivation for writing a review article is to make a comprehensive synthesis of the most appropriate literature on a specific research inquiry or topic. Thus, conducting a literature review assists in demonstrating the author's knowledge about a particular field of study, which may include but not be limited to its history, theories, key variables, vocabulary, phenomena, and methodologies [ 10 ]. Furthermore, publishing reviews is beneficial as it permits the researchers to examine different questions and, as a result, enhances the depth and diversity of their scientific reasoning [ 1 ]. In addition, writing review articles allows researchers to share insights with the scientific community while identifying knowledge gaps to be addressed in future research. The review writing process can also be a useful tool in training early-career scientists in leadership, coordination, project management, and other important soft skills necessary for success in the research world [ 13 ]. Another important reason for authoring reviews is that such publications have been observed to be remarkably influential, extending the reach of an author in multiple folds of what can be achieved by primary research papers [ 1 ]. The trend in science is for authors to receive more citations from their review articles than from their original research articles. According to Miranda and Garcia-Carpintero [ 14 ], review articles are, on average, three times more frequently cited than original research articles; they also asserted that a 20% increase in review authorship could result in a 40–80% increase in citations of the author. As a result, writing reviews can significantly impact a researcher's citation output and serve as a valuable channel to reach a wider scientific audience. In addition, the references cited in a review article also provide the reader with an opportunity to dig deeper into the topic of interest. Thus, review articles can serve as a valuable repository for consultation, increasing the visibility of the authors and resulting in more citations.

3. Types of Review Articles

The first step in writing a good literature review is to decide on the particular type of review to be written; hence, it is important to distinguish and understand the various types of review articles. Although scientific review articles have been classified according to various schemes, however, they are broadly categorised into narrative reviews, systematic reviews, and meta-analyses [ 15 ]. It was observed that more authors—as well as publishers—were leaning towards systematic reviews and meta-analysis while downplaying narrative reviews; however, the three serve different aims and should all be considered equally important in science [ 1 ]. Bibliometric reviews and patent reviews, which are closely related to meta-analysis, have also gained significant attention recently. However, from another angle, a review could also be of two types. In the first class, authors could deal with a widely studied topic where there is already an accumulated body of knowledge that requires analysis and synthesis [ 3 ]. At the other end of the spectrum, the authors may have to address an emerging issue that would benefit from exposure to potential theoretical foundations; hence, their contribution would arise from the fresh theoretical foundations proposed in developing a conceptual model [ 3 ].

3.1. Narrative Reviews

Narrative reviewers are mainly focused on providing clarification and critical analysis on a particular topic or body of literature through interpretative synthesis, creativity, and expert judgement. According to Green et al. [ 16 ], a narrative review can be in the form of editorials, commentaries, and narrative overviews. However, editorials and commentaries are usually expert opinions; hence, a beginner is more likely to write a narrative overview, which is more general and is also referred to as an unsystematic narrative review. Similarly, the literature review section of most dissertations and empirical papers is typically narrative in nature. Typically, narrative reviews combine results from studies that may have different methodologies to address different questions or to formulate a broad theoretical formulation [ 1 ]. They are largely integrative as strong focus is placed on the assimilation and synthesis of various aspects in the review, which may involve comparing and contrasting research findings or deriving structured implications [ 17 ]. In addition, they are also qualitative studies because they do not follow strict selection processes; hence, choosing publications is relatively more subjective and unsystematic [ 18 ]. However, despite their popularity, there are concerns about their inherent subjectivity. In many instances, when the supporting data for narrative reviews are examined more closely, the evaluations provided by the author(s) become quite questionable [ 19 ]. Nevertheless, if the goal of the author is to formulate a new theory that connects diverse strands of research, a narrative method is most appropriate.

3.2. Systematic Reviews

In contrast to narrative reviews, which are generally descriptive, systematic reviews employ a systematic approach to summarise evidence on research questions. Hence, systematic reviews make use of precise and rigorous criteria to identify, evaluate, and subsequently synthesise all relevant literature on a particular topic [ 12 , 20 ]. As a result, systematic reviews are more likely to inspire research ideas by identifying knowledge gaps or inconsistencies, thus helping the researcher to clearly define the research hypotheses or questions [ 21 ]. Furthermore, systematic reviews may serve as independent research projects in their own right, as they follow a defined methodology to search and combine reliable results to synthesise a new database that can be used for a variety of purposes [ 22 ]. Typically, the peculiarities of the individual reviewer, different search engines, and information databases used all ensure that no two searches will yield the same systematic results even if the searches are conducted simultaneously and under identical criteria [ 11 ]. Hence, attempts are made at standardising the exercise via specific methods that would limit bias and chance effects, prevent duplications, and provide more accurate results upon which conclusions and decisions can be made.

The most established of these methods is the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines which objectively defined statements, guidelines, reporting checklists, and flowcharts for undertaking systematic reviews as well as meta-analysis [ 23 ]. Though mainly designed for research in medical sciences, the PRISMA approach has gained wide acceptance in other fields of science and is based on eight fundamental propositions. These include the explicit definition of the review question, an unambiguous outline of the study protocol, an objective and exhaustive systematic review of reputable literature, and an unambiguous identification of included literature based on defined selection criteria [ 24 ]. Other considerations include an unbiased appraisal of the quality of the selected studies (literature), organic synthesis of the evidence of the study, preparation of the manuscript based on the reporting guidelines, and periodic update of the review as new data emerge [ 24 ]. Other methods such as PRISMA-P (Preferred Reporting Items for Systematic review and Meta-Analysis Protocols), MOOSE (Meta-analysis Of Observational Studies in Epidemiology), and ROSES (Reporting Standards for Systematic Evidence Syntheses) have since been developed for systematic reviews (and meta-analysis), with most of them being derived from PRISMA.

Consequently, systematic reviews—unlike narrative reviews—must contain a methodology section which in addition to all that was highlighted above must fully describe the precise criteria used in formulating the research question and setting the inclusion or exclusion criteria used in selecting/accessing the literature. Similarly, the criteria for evaluating the quality of the literature included in the review as well as for analysing, synthesising, and disseminating the findings must be fully described in the methodology section.

3.3. Meta-Analysis

Meta-analyses are considered as more specialised forms of systematic reviews. Generally, they combine the results of many studies that use similar or closely related methods to address the same question or share a common quantitative evaluation method [ 25 ]. However, meta-analyses are also a step higher than other systematic reviews as they are focused on numerical data and involve the use of statistics in evaluating different studies and synthesising new knowledge. The major advantage of this type of review is the increased statistical power leading to more reliable results for inferring modest associations and a more comprehensive understanding of the true impact of a research study [ 26 ]. Unlike in traditional systematic reviews, research topics covered in meta-analyses must be mature enough to allow the inclusion of sufficient homogeneous empirical research in terms of subjects, interventions, and outcomes [ 27 , 28 ].

Being an advanced form of systematic review, meta-analyses must also have a distinct methodology section; hence, the standard procedures involved in the traditional systematic review (especially PRISMA) also apply in meta-analyses [ 23 ]. In addition to the common steps in formulating systematic reviews, meta-analyses are required to describe how nested and missing data are handled, the effect observed in each study, the confidence interval associated with each synthesised effect, and any potential for bias presented within the sample(s) [ 17 ]. According to Paul and Barari [ 28 ], a meta-analysis must also detail the final sample, the meta-analytic model, and the overall analysis, moderator analysis, and software employed. While the overall analysis involves the statistical characterization of the relationships between variables in the meta-analytic framework and their significance, the moderator analysis defines the different variables that may affect variations in the original studies [ 28 , 29 ]. It must also be noted that the accuracy and reliability of meta-analyses have both been significantly enhanced by the incorporation of statistical approaches such as Bayesian analysis [ 30 ], network analysis [ 31 ], and more recently, machine learning [ 32 ].

3.4. Bibliometric Review

A bibliometric review, commonly referred to as bibliometric analysis, is a systematic evaluation of published works within a specific field or discipline [ 33 ]. This bibliometric methodology involves the use of quantitative methods to analyse bibliometric data such as the characteristics and numbers of publications, units of citations, authorship, co-authorship, and journal impact factors [ 34 ]. Academics use bibliometric analysis with different objectives in mind, which includes uncovering emerging trends in article and journal performance, elaborating collaboration patterns and research constituents, evaluating the impact and influence of particular authors, publications, or research groups, and highlighting the intellectual framework of a certain field [ 35 ]. It is also used to inform policy and decision-making. Similarly to meta-analysis, bibliometric reviews rely upon quantitative techniques, thus avoiding the interpretation bias that could arise from the qualitative techniques of other types of reviews [ 36 ]. However, while bibliometric analysis synthesises the bibliometric and intellectual structure of a field by examining the social and structural linkages between various research parts, meta-analysis focuses on summarising empirical evidence by probing the direction and strength of effects and relationships among variables, especially in open research questions [ 37 , 38 ]. However, similarly to systematic review and meta-analysis, a bibliometric review also requires a well-detailed methodology section. The amount of data to be analysed in bibliometric analysis is quite massive, running to hundreds and tens of thousands in some cases. Although the data are objective in nature (e.g., number of citations and publications and occurrences of keywords and topics), the interpretation is usually carried out through both objective (e.g., performance analysis) and subjective (e.g., thematic analysis) evaluations [ 35 ]. However, the invention and availability of bibliometric software such as BibExcel, Gephi, Leximancer, and VOSviewer and scientific databases such as Dimensions, Web of Science, and Scopus have made this type of analysis more feasible.

3.5. Patent Review

Patent reviews provide a comprehensive analysis and critique of a specific patent or a group of related patents, thus presenting a concise understanding of the technology or innovation that is covered by the patent [ 39 ]. This type of article is useful for researchers as it also enhances their understanding of the legal, technical, and commercial aspects of an intellectual property/innovation; in addition, it is also important for stakeholders outside the research community including IP (intellectual property) specialists, legal professionals, and technology-transfer officers [ 40 ]. Typically, patent reviews encompass the scope, background, claims, legal implications, technical specifications, and potential commercial applications of the patent(s). The article may also include a discussion of the patent's strengths and weaknesses, as well as its potential impact on the industry or field in which it operates. Most times, reviews are time specified, they may be regionalised, and the data are usually retrieved via patent searches on databases such as that of the European Patent Office ( https://www.epo.org/searching.html ), United States Patent and Trademark Office ( https://patft.uspto.gov/ ), the World Intellectual Property Organization's PATENTSCOPE ( https://patentscope.wipo.int/search/en/structuredSearch.jsf ), Google Patent ( https://www.google.com/?tbm=pts ), and China National Intellectual Property Administration ( https://pss-system.cponline.cnipa.gov.cn/conventionalSearch ). According to Cerimi et al. [ 41 ], the retrieved data and analysed may include the patent number, patent status, filing date, application date, grant dates, inventor, assignee, and pending applications. While data analysis is usually carried out by general data software such as Microsoft Excel, an intelligence software solely dedicated to patent research and analysis, Orbit Intelligence has been found to be more efficient [ 39 ]. It is also mandatory to include a methodology section in a patent review, and this should be explicit, thorough, and precise to allow a clear understanding of how the analysis was carried out and how the conclusions were arrived at.

4. Searching Literature

One of the most challenging tasks in writing a review article on a subject is the search for relevant literature to populate the manuscript as the author is required to garner information from an endless number of sources. This is even more challenging as research outputs have been increasing astronomically, especially in the last decade, with thousands of new articles published annually in various fields. It is therefore imperative that the author must not only be aware of the overall trajectory in a field of investigation but must also be cognizant of recent studies so as not to publish outdated research or review articles. Basically, the search for the literature involves a coherent conceptual structuring of the topic itself and a thorough collation of evidence under the common themes which might reflect the histories, conflicts, standoffs, revolutions, and/or evolutions in the field [ 7 ]. To start the search process, the author must carefully identify and select broad keywords relevant to the subject; subsequently, the keywords should be developed to refine the search into specific subheadings that would facilitate the structure of the review.

Two main tactics have been identified for searching the literature, namely, systematic and snowballing [ 42 ]. The systematic approach involves searching literature with specific keywords (for example, cancer, antioxidant, and nanoparticles), which leads to an almost unmanageable and overwhelming list of possible sources [ 43 ]. The snowballing approach, however, involves the identification of a particular publication, followed by the compilation of a bibliography of articles based on the reference list of the identified publication [ 44 ]. Many times, it might be necessary to combine both approaches, but irrespective, the author must keep an accurate track and record of papers cited in the search. A simple and efficient strategy for populating the bibliography of review articles is to go through the abstract (and sometimes the conclusion) of a paper; if the abstract is related to the topic of discourse, the author might go ahead and read the entire article; otherwise, he/she is advised to move on [ 45 ]. Winchester and Salji [ 5 ] noted that to learn the background of the subject/topic to be reviewed, starting literature searches with academic textbooks or published review articles is imperative, especially for beginners. Furthermore, it would also assist in compiling the list of keywords, identifying areas of further exploration, and providing a glimpse of the current state of the research. However, past reviews ideally are not to serve as the foundation of a new review as they are written from someone else's viewpoint, which might have been tainted with some bias. Fortunately, the accessibility and search for the literature have been made relatively easier than they were a few decades ago as the current information age has placed an enormous volume of knowledge right at our fingertips [ 46 ]. Nevertheless, when gathering the literature from the Internet, authors should exercise utmost caution as much of the information may not be verified or peer-reviewed and thus may be unregulated and unreliable. For instance, Wikipedia, despite being a large repository of information with more than 6.7 million articles in the English language alone, is considered unreliable for scientific literature reviews, due to its openness to public editing [ 47 ]. However, in addition to peer-reviewed journal publications—which are most ideal—reviews can also be drawn from a wide range of other sources such as technical documents, in-house reports, conference abstracts, and conference proceedings. Similarly, “Google Scholar”—as against “Google” and other general search engines—is more appropriate as its searches are restricted to only academic articles produced by scholarly societies or/and publishers [ 48 ]. Furthermore, the various electronic databases, such as ScienceDirect, Web of Science, PubMed, and MEDLINE, many of which focus on specific fields of research, are also ideal options [ 49 ]. Advancement in computer indexing has remarkably expanded the ease and ability to search large databases for every potentially relevant article. In addition to searching by topic, literature search can be modified by time; however, there must be a balance between old papers and recent ones. The general consensus in science is that publications less than five years old are considered recent.

It is important, especially in systematic reviews and meta-analyses, that the specific method of running the computer searches be properly documented as there is the need to include this in the method (methodology) section of such papers. Typically, the method details the keywords, databases explored, search terms used, and the inclusion/exclusion criteria applied in the selection of data and any other specific decision/criteria. All of these will ensure the reproducibility and thoroughness of the search and the selection procedure. However, Randolph [ 10 ] noted that Internet searches might not give the exhaustive list of articles needed for a review article; hence, it is advised that authors search through the reference lists of articles that were obtained initially from the Internet search. After determining the relevant articles from the list, the author should read through the references of these articles and repeat the cycle until saturation is reached [ 10 ]. After populating the articles needed for the literature review, the next step is to analyse them individually and in their whole entirety. A systematic approach to this is to identify the key information within the papers, examine them in depth, and synthesise original perspectives by integrating the information and making inferences based on the findings. In this regard, it is imperative to link one source to the other in a logical manner, for instance, taking note of studies with similar methodologies, papers that agree, or results that are contradictory [ 42 ].

5. Structuring the Review Article

The title and abstract are the main selling points of a review article, as most readers will only peruse these two elements and usually go on to read the full paper if they are drawn in by either or both of the two. Tullu [ 50 ] recommends that the title of a scientific paper “should be descriptive, direct, accurate, appropriate, interesting, concise, precise, unique, and not be misleading.” In addition to providing “just enough details” to entice the reader, words in the titles are also used by electronic databases, journal websites, and search engines to index and retrieve a particular paper during a search [ 51 ]. Titles are of different types and must be chosen according to the topic under review. They are generally classified as descriptive, declarative, or interrogative and can also be grouped into compound, nominal, or full-sentence titles [ 50 ]. The subject of these categorisations has been extensively discussed in many articles; however, the reader must also be aware of the compound titles, which usually contain a main title and a subtitle. Typically, subtitles provide additional context—to the main title—and they may specify the geographic scope of the research, research methodology, or sample size [ 52 ].

Just like primary research articles, there are many debates about the optimum length of a review article's title. However, the general consensus is to keep the title as brief as possible while not being too general. A title length between 10 and 15 words is recommended, since longer titles can be more challenging to comprehend. Paiva et al. [ 53 ] observed that articles which contain 95 characters or less get more views and citations. However, emphasis must be placed on conciseness as the audience will be more satisfied if they can understand what exactly the review has contributed to the field, rather than just a hint about the general topic area. Authors should also endeavour to stick to the journal's specific requirements, especially regarding the length of the title and what they should or should not contain [ 9 ]. Thus, avoidance of filler words such as “a review on/of,” “an observation of,” or “a study of” is a very simple way to limit title length. In addition, abbreviations or acronyms should be avoided in the title, except the standard or commonly interpreted ones such as AIDS, DNA, HIV, and RNA. In summary, to write an effective title, the authors should consider the following points. What is the paper about? What was the methodology used? What were the highlights and major conclusions? Subsequently, the author should list all the keywords from these answers, construct a sentence from these keywords, and finally delete all redundant words from the sentence title. It is also possible to gain some ideas by scanning indices and article titles in major journals in the field. It is important to emphasise that a title is not chosen and set in stone, and the title is most likely to be continually revised and adjusted until the end of the writing process.

5.2. Abstract

The abstract, also referred to as the synopsis, is a summary of the full research paper; it is typically independent and can stand alone. For most readers, a publication does not exist beyond the abstract, partly because abstracts are often the only section of a paper that is made available to the readers at no cost, whereas the full paper may attract a payment or subscription [ 54 ]. Thus, the abstract is supposed to set the tone for the few readers who wish to read the rest of the paper. It has also been noted that the abstract gives the first impression of a research work to journal editors, conference scientific committees, or referees, who might outright reject the paper if the abstract is poorly written or inadequate [ 50 ]. Hence, it is imperative that the abstract succinctly represents the entire paper and projects it positively. Just like the title, abstracts have to be balanced, comprehensive, concise, functional, independent, precise, scholarly, and unbiased and not be misleading [ 55 ]. Basically, the abstract should be formulated using keywords from all the sections of the main manuscript. Thus, it is pertinent that the abstract conveys the focus, key message, rationale, and novelty of the paper without any compromise or exaggeration. Furthermore, the abstract must be consistent with the rest of the paper; as basic as this instruction might sound, it is not to be taken for granted. For example, a study by Vrijhoef and Steuten [ 56 ] revealed that 18–68% of 264 abstracts from some scientific journals contained information that was inconsistent with the main body of the publications.

Abstracts can either be structured or unstructured; in addition, they can further be classified as either descriptive or informative. Unstructured abstracts, which are used by many scientific journals, are free flowing with no predefined subheadings, while structured abstracts have specific subheadings/subsections under which the abstract needs to be composed. Structured abstracts have been noted to be more informative and are usually divided into subsections which include the study background/introduction, objectives, methodology design, results, and conclusions [ 57 ]. No matter the style chosen, the author must carefully conform to the instructions provided by the potential journal of submission, which may include but are not limited to the format, font size/style, word limit, and subheadings [ 58 ]. The word limit for abstracts in most scientific journals is typically between 150 and 300 words. It is also a general rule that abstracts do not contain any references whatsoever.

Typically, an abstract should be written in the active voice, and there is no such thing as a perfect abstract as it could always be improved on. It is advised that the author first makes an initial draft which would contain all the essential parts of the paper, which could then be polished subsequently. The draft should begin with a brief background which would lead to the research questions. It might also include a general overview of the methodology used (if applicable) and importantly, the major results/observations/highlights of the review paper. The abstract should end with one or few sentences about any implications, perspectives, or future research that may be developed from the review exercise. Finally, the authors should eliminate redundant words and edit the abstract to the correct word count permitted by the journal [ 59 ]. It is always beneficial to read previous abstracts published in the intended journal, related topics/subjects from other journals, and other reputable sources. Furthermore, the author should endeavour to get feedback on the abstract especially from peers and co-authors. As the abstract is the face of the whole paper, it is best that it is the last section to be finalised, as by this time, the author would have developed a clearer understanding of the findings and conclusions of the entire paper.

5.3. Graphical Abstracts

Since the mid-2000s, an increasing number of journals now require authors to provide a graphical abstract (GA) in addition to the traditional written abstract, to increase the accessibility of scientific publications to readers [ 60 ]. A study showed that publications with GA performed better than those without it, when the abstract views, total citations, and downloads were compared [ 61 ]. However, the GA should provide “a single, concise pictorial, and visual summary of the main findings of an article” [ 62 ]. Although they are meant to be a stand-alone summary of the whole paper, it has been noted that they are not so easily comprehensible without having read through the traditionally written abstract [ 63 ]. It is important to note that, like traditional abstracts, many reputable journals require GAs to adhere to certain specifications such as colour, dimension, quality, file size, and file format (usually JPEG/JPG, PDF, PNG, or TIFF). In addition, it is imperative to use engaging and accurate figures, all of which must be synthesised in order to accurately reflect the key message of the paper. Currently, there are various online or downloadable graphical tools that can be used for creating GAs, such as Microsoft Paint or PowerPoint, Mindthegraph, ChemDraw, CorelDraw, and BioRender.

5.4. Keywords

As a standard practice, journals require authors to select 4–8 keywords (or phrases), which are typically listed below the abstract. A good set of keywords will enable indexers and search engines to find relevant papers more easily and can be considered as a very concise abstract [ 64 ]. According to Dewan and Gupta [ 51 ], the selection of appropriate keywords will significantly enhance the retrieval, accession, and consequently, the citation of the review paper. Ideally, keywords can be variants of the terms/phrases used in the title, the abstract, and the main text, but they should ideally not be the exact words in the main title. Choosing the most appropriate keywords for a review article involves listing down the key terms and phrases in the article, including abbreviations. Subsequently, a quick review of the glossary/vocabulary/term list or indexing standard in the specific discipline will assist in selecting the best and most precise keywords that match those used in the databases from the list drawn. In addition, the keywords should not be broad or general terms (e.g., DNA, biology, and enzymes) but must be specific to the field or subfield of study as well as to the particular paper [ 65 ].

5.5. Introduction

The introduction of an article is the first major section of the manuscript, and it presents basic information to the reader without compelling them to study past publications. In addition, the introduction directs the reader to the main arguments and points developed in the main body of the article while clarifying the current state of knowledge in that particular area of research [ 12 ]. The introduction part of a review article is usually sectionalised into background information, a description of the main topic and finally a statement of the main purpose of the review [ 66 ]. Authors may begin the introduction with brief general statements—which provide background knowledge on the subject matter—that lead to more specific ones [ 67 ]. It is at this point that the reader's attention must be caught as the background knowledge must highlight the importance and justification for the subject being discussed, while also identifying the major problem to be addressed [ 68 ]. In addition, the background should be broad enough to attract even nonspecialists in the field to maximise the impact and widen the reach of the article. All of these should be done in the light of current literature; however, old references may also be used for historical purposes. A very important aspect of the introduction is clearly stating and establishing the research problem(s) and how a review of the particular topic contributes to those problem(s). Thus, the research gap which the paper intends to fill, the limitations of previous works and past reviews, if available, and the new knowledge to be contributed must all be highlighted. Inadequate information and the inability to clarify the problem will keep readers (who have the desire to obtain new information) from reading beyond the introduction [ 69 ]. It is also pertinent that the author establishes the purpose of reviewing the literature and defines the scope as well as the major synthesised point of view. Furthermore, a brief insight into the criteria used to select, evaluate, and analyse the literature, as well as the outline or sequence of the review, should be provided in the introduction. Subsequently, the specific objectives of the review article must be presented. The last part of the “introduction” section should focus on the solution, the way forward, the recommendations, and the further areas of research as deduced from the whole review process. According to DeMaria [ 70 ], clearly expressed or recommended solutions to an explicitly revealed problem are very important for the wholesomeness of the “introduction” section. It is believed that following these steps will give readers the opportunity to track the problems and the corresponding solution from their own perspective in the light of current literature. As against some suggestions that the introduction should be written only in present tenses, it is also believed that it could be done with other tenses in addition to the present tense. In this regard, general facts should be written in the present tense, specific research/work should be in the past tense, while the concluding statement should be in the past perfect or simple past. Furthermore, many of the abbreviations to be used in the rest of the manuscript and their explanations should be defined in this section.

5.6. Methodology

Writing a review article is equivalent to conducting a research study, with the information gathered by the author (reviewer) representing the data. Like all major studies, it involves conceptualisation, planning, implementation, and dissemination [ 71 ], all of which may be detailed in a methodology section, if necessary. Hence, the methodological section of a review paper (which can also be referred to as the review protocol) details how the relevant literature was selected and how it was analysed as well as summarised. The selection details may include, but are not limited to, the database consulted and the specific search terms used together with the inclusion/exclusion criteria. As earlier highlighted in Section 3 , a description of the methodology is required for all types of reviews except for narrative reviews. This is partly because unlike narrative reviews, all other review articles follow systematic approaches which must ensure significant reproducibility [ 72 ]. Therefore, where necessary, the methods of data extraction from the literature and data synthesis must also be highlighted as well. In some cases, it is important to show how data were combined by highlighting the statistical methods used, measures of effect, and tests performed, as well as demonstrating heterogeneity and publication bias [ 73 ].

The methodology should also detail the major databases consulted during the literature search, e.g., Dimensions, ScienceDirect, Web of Science, MEDLINE, and PubMed. For meta-analysis, it is imperative to highlight the software and/or package used, which could include Comprehensive Meta-Analysis, OpenMEE, Review Manager (RevMan), Stata, SAS, and R Studio. It is also necessary to state the mathematical methods used for the analysis; examples of these include the Bayesian analysis, the Mantel–Haenszel method, and the inverse variance method. The methodology should also state the number of authors that carried out the initial review stage of the study, as it has been recommended that at least two reviews should be done blindly and in parallel, especially when it comes to the acquisition and synthesis of data [ 74 ]. Finally, the quality and validity assessment of the publication used in the review must be stated and well clarified [ 73 ].

5.7. Main Body of the Review

Ideally, the main body of a publishable review should answer these questions: What is new (contribution)? Why so (logic)? So what (impact)? How well it is done (thoroughness)? The flow of the main body of a review article must be well organised to adequately maintain the attention of the readers as well as guide them through the section. It is recommended that the author should consider drawing a conceptual scheme of the main body first, using methods such as mind-mapping. This will help create a logical flow of thought and presentation, while also linking the various sections of the manuscript together. According to Moreira [ 75 ], “reports do not simply yield their findings, rather reviewers make them yield,” and thus, it is the author's responsibility to transform “resistant” texts into “docile” texts. Hence, after the search for the literature, the essential themes and key concepts of the review paper must be identified and synthesised together. This synthesis primarily involves creating hypotheses about the relationships between the concepts with the aim of increasing the understanding of the topic being reviewed. The important information from the various sources should not only be summarised, but the significance of studies must be related back to the initial question(s) posed by the review article. Furthermore, MacLure [ 76 ] stated that data are not just to be plainly “extracted intact” and “used exactly as extracted,” but must be modified, reconfigured, transformed, transposed, converted, tabulated, graphed, or manipulated to enable synthesis, combination, and comparison. Therefore, different pieces of information must be extracted from the reports in which they were previously deposited and then refined into the body of the new article [ 75 ]. To this end, adequate comparison and combination might require that “qualitative data be quantified” or/and “quantitative data may be qualitized” [ 77 ]. In order to accomplish all of these goals, the author may have to transform, paraphrase, generalize, specify, and reorder the text [ 78 ]. For comprehensiveness, the body paragraphs should be arranged in a similar order as it was initially stated in the abstract or/and introduction. Thus, the main body could be divided into thematic areas, each of which could be independently comprehensive and treated as a mini review. Similarly, the sections can also be arranged chronologically depending on the focus of the review. Furthermore, the abstractions should proceed from a wider general view of the literature being reviewed and then be narrowed down to the specifics. In the process, deep insights should also be provided between the topic of the review and the wider subject area, e.g., fungal enzymes and enzymes in general. The abstractions must also be discussed in more detail by presenting more specific information from the identified sources (with proper citations of course!). For example, it is important to identify and highlight contrary findings and rival interpretations as well as to point out areas of agreement or debate among different bodies of literature. Often, there are previous reviews on the same topic/concept; however, this does not prevent a new author from writing one on the same topic, especially if the previous reviews were written many years ago. However, it is important that the body of the new manuscript be written from a new angle that was not adequately covered in the past reviews and should also incorporate new studies that have accumulated since the last review(s). In addition, the new review might also highlight the approaches, limitations, and conclusions of the past studies. But the authors must not be excessively critical of the past reviews as this is regarded by many authors as a sign of poor professionalism [ 3 , 79 ]. Daft [ 79 ] emphasized that it is more important for a reviewer to state how their research builds on previous work instead of outright claiming that previous works are incompetent and inadequate. However, if a series of related papers on one topic have a common error or research flaw that needs rectification, the reviewer must point this out with the aim of moving the field forward [ 3 ]. Like every other scientific paper, the main body of a review article also needs to be consistent in style, for example, in the choice of passive vs. active voice and present vs. past tense. It is also important to note that tables and figures can serve as a powerful tool for highlighting key points in the body of the review, and they are now considered core elements of reviews. For more guidance and insights into what should make up the contents of a good review article, readers are also advised to get familiarised with the Boote and Beile [ 80 ] literature review scoring rubric as well as the review article checklist of Short [ 81 ].

5.8. Tables and Figures

An ideal review article should be logically structured and efficiently utilise illustrations, in the form of tables and figures, to convey the key findings and relationships in the study. According to Tay [ 13 ], illustrations often take a secondary role in review papers when compared to primary research papers which are focused on illustrations. However, illustrations are very important in review articles as they can serve as succinct means of communicating major findings and insights. Franzblau and Chung [ 82 ] pointed out that illustrations serve three major purposes in a scientific article: they simplify complex data and relationships for better understanding, they minimise reading time by summarising and bringing to focus on the key findings (or trends), and last, they help to reduce the overall word count. Hence, inserting and constructing illustrations in a review article is as meticulous as it is important. However, important decisions should be made on whether the charts, figures, or tables to be potentially inserted in the manuscript are indeed needed and how best to design them [ 83 ]. Illustrations should enhance the text while providing necessary information; thus, the information described in illustrations should not contradict that in the main text and should also not be a repetition of texts [ 84 ]. Furthermore, illustrations must be autonomous, meaning they ought to be intelligible without having to read the text portion of the manuscript; thus, the reader does not have to flip back and forth between the illustration and the main text in order to understand it [ 85 ]. It should be noted that tables or figures that directly reiterate the main text or contain extraneous information will only make a mess of the manuscript and discourage readers [ 86 ].

Kotz and Cals [ 87 ] recommend that the layout of tables and figures should be carefully designed in a clear manner with suitable layouts, which will allow them to be referred to logically and chronologically in the text. In addition, illustrations should only contain simple text, as lengthy details would contradict their initial objective, which was to provide simple examples or an overview. Furthermore, the use of abbreviations in illustrations, especially tables, should be avoided if possible. If not, the abbreviations should be defined explicitly in the footnotes or legends of the illustration [ 88 ]. Similarly, numerical values in tables and graphs should also be correctly approximated [ 84 ]. It is recommended that the number of tables and figures in the manuscript should not exceed the target journal's specification. According to Saver [ 89 ], they ideally should not account for more than one-third of the manuscript. Finally, the author(s) must seek permission and give credits for using an already published illustration when necessary. However, none of these are needed if the graphic is originally created by the author, but if it is a reproduced or an adapted illustration, the author must obtain permission from the copyright owner and include the necessary credit. One of the very important tools for designing illustrations is Creative Commons, a platform that provides a wide range of creative works which are available to the public for use and modification.

5.9. Conclusion/Future Perspectives

It has been observed that many reviews end abruptly with a short conclusion; however, a lot more can be included in this section in addition to what has been said in the major sections of the paper. Basically, the conclusion section of a review article should provide a summary of key findings from the main body of the manuscript. In this section, the author needs to revisit the critical points of the paper as well as highlight the accuracy, validity, and relevance of the inferences drawn in the article review. A good conclusion should highlight the relationship between the major points and the author's hypothesis as well as the relationship between the hypothesis and the broader discussion to demonstrate the significance of the review article in a larger context. In addition to giving a concise summary of the important findings that describe current knowledge, the conclusion must also offer a rationale for conducting future research [ 12 ]. Knowledge gaps should be identified, and themes should be logically developed in order to construct conceptual frameworks as well as present a way forward for future research in the field of study [ 11 ].

Furthermore, the author may have to justify the propositions made earlier in the manuscript, demonstrate how the paper extends past research works, and also suggest ways that the expounded theories can be empirically examined [ 3 ]. Unlike experimental studies which can only draw either a positive conclusion or ambiguous failure to reject the null hypothesis, four possible conclusions can be drawn from review articles [ 1 ]. First, the theory/hypothesis propounded may be correct after being proven from current evidence; second, the hypothesis may not be explicitly proven but is most probably the best guess. The third conclusion is that the currently available evidence does not permit a confident conclusion or a best guess, while the last conclusion is that the theory or hypothesis is false [ 1 ]. It is important not to present new information in the conclusion section which has link whatsoever with the rest of the manuscript. According to Harris et al. [ 90 ], the conclusions should, in essence, answer the question: if a reader were to remember one thing about the review, what would it be?

5.10. References

As it has been noted in different parts of this paper, authors must give the required credit to any work or source(s) of information that was included in the review article. This must include the in-text citations in the main body of the paper and the corresponding entries in the reference list. Ideally, this full bibliographical list is the last part of the review article, and it should contain all the books, book chapters, journal articles, reports, and other media, which were utilised in the manuscript. It has been noted that most journals and publishers have their own specific referencing styles which are all derived from the more popular styles such as the American Psychological Association (APA), Chicago, Harvard, Modern Language Association (MLA), and Vancouver styles. However, all these styles may be categorised into either the parenthetical or numerical referencing style. Although a few journals do not have strict referencing rules, it is the responsibility of the author to reference according to the style and instructions of the journal. Omissions and errors must be avoided at all costs, and this can be easily achieved by going over the references many times for due diligence [ 11 ]. According to Cronin et al. [ 12 ], a separate file for references can be created, and any work used in the manuscript can be added to this list immediately after being cited in the text [ 12 ]. In recent times, the emergence of various referencing management software applications such as Endnote, RefWorks, Mendeley, and Zotero has even made referencing easier. The majority of these software applications require little technical expertise, and many of them are free to use, while others may require a subscription. It is imperative, however, that even after using these software packages, the author must manually curate the references during the final draft, in order to avoid any errors, since these programs are not impervious to errors, particularly formatting errors.

6. Concluding Remarks

Writing a review article is a skill that needs to be learned; it is a rigorous but rewarding endeavour as it can provide a useful platform to project the emerging researcher or postgraduate student into the gratifying world of publishing. Thus, the reviewer must develop the ability to think critically, spot patterns in a large volume of information, and must be invested in writing without tiring. The prospective author must also be inspired and dedicated to the successful completion of the article while also ensuring that the review article is not just a mere list or summary of previous research. It is also important that the review process must be focused on the literature and not on the authors; thus, overt criticism of existing research and personal aspersions must be avoided at all costs. All ideas, sentences, words, and illustrations should be constructed in a way to avoid plagiarism; basically, this can be achieved by paraphrasing, summarising, and giving the necessary acknowledgments. Currently, there are many tools to track and detect plagiarism in manuscripts, ensuring that they fall within a reasonable similarity index (which is typically 15% or lower for most journals). Although the more popular of these tools, such as Turnitin and iThenticate, are subscription-based, there are many freely available web-based options as well. An ideal review article is supposed to motivate the research topic and describe its key concepts while delineating the boundaries of research. In this regard, experience-based information on how to methodologically develop acceptable and impactful review articles has been detailed in this paper. Furthermore, for a beginner, this guide has detailed “the why” and “the how” of authoring a good scientific review article. However, the information in this paper may as a whole or in parts be also applicable to other fields of research and to other writing endeavours such as writing literature review in theses, dissertations, and primary research articles. Finally, the intending authors must put all the basic rules of scientific writing and writing in general into cognizance. A comprehensive study of the articles cited within this paper and other related articles focused on scientific writing will further enhance the ability of the motivated beginner to deliver a good review article.


This work was supported by the National Research Foundation of South Africa under grant number UID 138097. The authors would like to thank the Durban University of Technology for funding the postdoctoral fellowship of the first author, Dr. Ayodeji Amobonye.

Data Availability

Conflicts of interest.

The authors declare that they have no conflicts of interest.

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Characteristics of a Primary Research Article

  • Goal is to present the result of original research that makes a new contribution to the body of knowledge
  • Sometimes referred to as an empirical research article
  • Typically organized into sections that include:  Abstract, Introduction, Methods, Results, Discussion/Conclusion, and References.

Example of a Primary Research Article:

Flockhart, D.T.T., Fitz-gerald, B., Brower, L.P., Derbyshire, R., Altizer, S., Hobson, K.A., … Norris, D.R., (2017). Migration distance as a selective episode for wing morphology in a migratory insect. Movement Ecology , 5(1), 1-9. doi: doi.org/10.1186/s40462-017-0098-9

Characteristics of a Review Article

  • Goal is to summarize important research on a particular topic and to represent the current body of knowledge about that topic.
  • Not intended to provide original research but to help draw connections between research studies that have previously been published.  
  • Help the reader understand how current understanding of a topic has developed over time and identify gaps or inconsistencies that need further exploration.

Example of a Review Article:


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Science Research: Primary Sources and Original Research vs. Review Articles

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Original Research vs. Review Articles. How can I tell the Difference?

Research vs review articles.

It's often difficult to tell the difference between original research articles and review articles. Here are some explanations and tips that may help: "Review articles are often as lengthy or even longer that original research articles. What the authors of review articles are doing in analysing and evaluating current research and investigations related to a specific topic, field, or problem. They are not primary sources since they review previously published material. They can be of great value for identifying potentially good primary sources, but they aren't primary themselves. Primary research articles can be identified by a commonly used format. If an article contains the following elements, you can count on it being a primary research article. Look for sections titled:

Methods (sometimes with variations, such as Materials and Methods) Results (usually followed with charts and statistical tables) Discussion

You can also read the abstract to get a good sense of the kind of article that is being presented.

If it is a review article instead of a research article, the abstract should make that pretty clear. If there is no abstract at all, that in itself may be a sign that it is not a primary resource. Short research articles, such as those found in Science and similar scientific publications that mix news, editorials, and forums with research reports, however, may not include any of those elements. In those cases look at the words the authors use, phrases such as "we tested"  and "in our study, we measured" will tell you that the article is reporting on original research."*

*Taken from Ithca College Libraries

Primary and Secondary Sources for Science

In the Sciences, primary sources are documents that provide full description of the original research. For example, a primary source would be a journal article where scientists describe their research on the human immune system. A secondary source would be an article commenting or analyzing the scientists' research on the human immune system.


Source: The Evolution of Scientific Information (from  Encyclopedia of Library and Information Science , vol. 26).

Primary Vs. Secondary Vs. Tertiary Sources

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Q. What's the difference between a research article (or research study) and a review article?


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Answered By: Priscilla Coulter Last Updated: Jul 29, 2022     Views: 232414

A research paper is a primary source ...that is, it reports the methods and results of an original study performed by the authors . The kind of study may vary (it could have been an experiment, survey, interview, etc.), but in all cases, raw data have been collected and analyzed by the authors , and conclusions drawn from the results of that analysis.

Research papers follow a particular format.  Look for:

  • A brief introduction will often include a review of the existing literature on the topic studied, and explain the rationale of the author's study.  This is important because it demonstrates that the authors are aware of existing studies, and are planning to contribute to this existing body of research in a meaningful way (that is, they're not just doing what others have already done).
  • A methods section, where authors describe how they collected and analyzed data.  Statistical analyses are included.  This section is quite detailed, as it's important that other researchers be able to verify and/or replicate these methods.
  • A results section describes the outcomes of the data analysis.  Charts and graphs illustrating the results are typically included.
  • In the discussion , authors will explain their interpretation of their results and theorize on their importance to existing and future research.
  • References or works cited are always included.  These are the articles and books that the authors drew upon to plan their study and to support their discussion.

You can use the library's article databases to search for research articles:

  • A research article will nearly always be published in a peer-reviewed journal; click here for instructions on limiting your searches to peer-reviewed articles.  
  • If you have a particular type of study in mind, you can include keywords to describe it in your search .  For instance, if you would like to see studies that used surveys to collect data, you can add "survey" to your topic in the database's search box. See this example search in our EBSCO databases: " bullying and survey ".   
  • Several of our databases have special limiting options that allow you to select specific methodologies.  See, for instance, the " Methodology " box in ProQuest's PsycARTICLES Advanced Search (scroll down a bit to see it).  It includes options like "Empirical Study" and "Qualitative Study", among many others.  

A review article is a secondary source ...it is written about other articles, and does not report original research of its own.  Review articles are very important, as they draw upon the articles that they review to suggest new research directions, to strengthen support for existing theories and/or identify patterns among exising research studies.  For student researchers, review articles provide a great overview of the existing literature on a topic.    If you find a literature review that fits your topic, take a look at its references/works cited list for leads on other relevant articles and books!

You can use the library's article databases to find literature reviews as well!  Click here for tips.

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Review articles: purpose, process, and structure

  • Published: 02 October 2017
  • Volume 46 , pages 1–5, ( 2018 )

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  • Robert W. Palmatier 1 ,
  • Mark B. Houston 2 &
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Many research disciplines feature high-impact journals that are dedicated outlets for review papers (or review–conceptual combinations) (e.g., Academy of Management Review , Psychology Bulletin , Medicinal Research Reviews ). The rationale for such outlets is the premise that research integration and synthesis provides an important, and possibly even a required, step in the scientific process. Review papers tend to include both quantitative (i.e., meta-analytic, systematic reviews) and narrative or more qualitative components; together, they provide platforms for new conceptual frameworks, reveal inconsistencies in the extant body of research, synthesize diverse results, and generally give other scholars a “state-of-the-art” snapshot of a domain, often written by topic experts (Bem 1995 ). Many premier marketing journals publish meta-analytic review papers too, though authors often must overcome reviewers’ concerns that their contributions are limited due to the absence of “new data.” Furthermore, relatively few non-meta-analysis review papers appear in marketing journals, probably due to researchers’ perceptions that such papers have limited publication opportunities or their beliefs that the field lacks a research tradition or “respect” for such papers. In many cases, an editor must provide strong support to help such review papers navigate the review process. Yet, once published, such papers tend to be widely cited, suggesting that members of the field find them useful (see Bettencourt and Houston 2001 ).

In this editorial, we seek to address three topics relevant to review papers. First, we outline a case for their importance to the scientific process, by describing the purpose of review papers . Second, we detail the review paper editorial initiative conducted over the past two years by the Journal of the Academy of Marketing Science ( JAMS ), focused on increasing the prevalence of review papers. Third, we describe a process and structure for systematic ( i.e. , non-meta-analytic) review papers , referring to Grewal et al. ( 2018 ) insights into parallel meta-analytic (effects estimation) review papers. (For some strong recent examples of marketing-related meta-analyses, see Knoll and Matthes 2017 ; Verma et al. 2016 ).

Purpose of review papers

In their most general form, review papers “are critical evaluations of material that has already been published,” some that include quantitative effects estimation (i.e., meta-analyses) and some that do not (i.e., systematic reviews) (Bem 1995 , p. 172). They carefully identify and synthesize relevant literature to evaluate a specific research question, substantive domain, theoretical approach, or methodology and thereby provide readers with a state-of-the-art understanding of the research topic. Many of these benefits are highlighted in Hanssens’ ( 2018 ) paper titled “The Value of Empirical Generalizations in Marketing,” published in this same issue of JAMS.

The purpose of and contributions associated with review papers can vary depending on their specific type and research question, but in general, they aim to

Resolve definitional ambiguities and outline the scope of the topic.

Provide an integrated, synthesized overview of the current state of knowledge.

Identify inconsistencies in prior results and potential explanations (e.g., moderators, mediators, measures, approaches).

Evaluate existing methodological approaches and unique insights.

Develop conceptual frameworks to reconcile and extend past research.

Describe research insights, existing gaps, and future research directions.

Not every review paper can offer all of these benefits, but this list represents their key contributions. To provide a sufficient contribution, a review paper needs to achieve three key standards. First, the research domain needs to be well suited for a review paper, such that a sufficient body of past research exists to make the integration and synthesis valuable—especially if extant research reveals theoretical inconsistences or heterogeneity in its effects. Second, the review paper must be well executed, with an appropriate literature collection and analysis techniques, sufficient breadth and depth of literature coverage, and a compelling writing style. Third, the manuscript must offer significant new insights based on its systematic comparison of multiple studies, rather than simply a “book report” that describes past research. This third, most critical standard is often the most difficult, especially for authors who have not “lived” with the research domain for many years, because achieving it requires drawing some non-obvious connections and insights from multiple studies and their many different aspects (e.g., context, method, measures). Typically, after the “review” portion of the paper has been completed, the authors must spend many more months identifying the connections to uncover incremental insights, each of which takes time to detail and explicate.

The increasing methodological rigor and technical sophistication of many marketing studies also means that they often focus on smaller problems with fewer constructs. By synthesizing these piecemeal findings, reconciling conflicting evidence, and drawing a “big picture,” meta-analyses and systematic review papers become indispensable to our comprehensive understanding of a phenomenon, among both academic and practitioner communities. Thus, good review papers provide a solid platform for future research, in the reviewed domain but also in other areas, in that researchers can use a good review paper to learn about and extend key insights to new areas.

This domain extension, outside of the core area being reviewed, is one of the key benefits of review papers that often gets overlooked. Yet it also is becoming ever more important with the expanding breadth of marketing (e.g., econometric modeling, finance, strategic management, applied psychology, sociology) and the increasing velocity in the accumulation of marketing knowledge (e.g., digital marketing, social media, big data). Against this backdrop, systematic review papers and meta-analyses help academics and interested managers keep track of research findings that fall outside their main area of specialization.

JAMS’ review paper editorial initiative

With a strong belief in the importance of review papers, the editorial team of JAMS has purposely sought out leading scholars to provide substantive review papers, both meta-analysis and systematic, for publication in JAMS . Many of the scholars approached have voiced concerns about the risk of such endeavors, due to the lack of alternative outlets for these types of papers. Therefore, we have instituted a unique process, in which the authors develop a detailed outline of their paper, key tables and figures, and a description of their literature review process. On the basis of this outline, we grant assurances that the contribution hurdle will not be an issue for publication in JAMS , as long as the authors execute the proposed outline as written. Each paper still goes through the normal review process and must meet all publication quality standards, of course. In many cases, an Area Editor takes an active role to help ensure that each paper provides sufficient insights, as required for a high-quality review paper. This process gives the author team confidence to invest effort in the process. An analysis of the marketing journals in the Financial Times (FT 50) journal list for the past five years (2012–2016) shows that JAMS has become the most common outlet for these papers, publishing 31% of all review papers that appeared in the top six marketing journals.

As a next step in positioning JAMS as a receptive marketing outlet for review papers, we are conducting a Thought Leaders Conference on Generalizations in Marketing: Systematic Reviews and Meta-Analyses , with a corresponding special issue (see www.springer.com/jams ). We will continue our process of seeking out review papers as an editorial strategy in areas that could be advanced by the integration and synthesis of extant research. We expect that, ultimately, such efforts will become unnecessary, as authors initiate review papers on topics of their own choosing to submit them to JAMS . In the past two years, JAMS already has increased the number of papers it publishes annually, from just over 40 to around 60 papers per year; this growth has provided “space” for 8–10 review papers per year, reflecting our editorial target.

Consistent with JAMS ’ overall focus on managerially relevant and strategy-focused topics, all review papers should reflect this emphasis. For example, the domains, theories, and methods reviewed need to have some application to past or emerging managerial research. A good rule of thumb is that the substantive domain, theory, or method should attract the attention of readers of JAMS .

The efforts of multiple editors and Area Editors in turn have generated a body of review papers that can serve as useful examples of the different types and approaches that JAMS has published.

Domain-based review papers

Domain-based review papers review, synthetize, and extend a body of literature in the same substantive domain. For example, in “The Role of Privacy in Marketing” (Martin and Murphy 2017 ), the authors identify and define various privacy-related constructs that have appeared in recent literature. Then they examine the different theoretical perspectives brought to bear on privacy topics related to consumers and organizations, including ethical and legal perspectives. These foundations lead in to their systematic review of privacy-related articles over a clearly defined date range, from which they extract key insights from each study. This exercise of synthesizing diverse perspectives allows these authors to describe state-of-the-art knowledge regarding privacy in marketing and identify useful paths for research. Similarly, a new paper by Cleeren et al. ( 2017 ), “Marketing Research on Product-Harm Crises: A Review, Managerial Implications, and an Agenda for Future Research,” provides a rich systematic review, synthesizes extant research, and points the way forward for scholars who are interested in issues related to defective or dangerous market offerings.

Theory-based review papers

Theory-based review papers review, synthetize, and extend a body of literature that uses the same underlying theory. For example, Rindfleisch and Heide’s ( 1997 ) classic review of research in marketing using transaction cost economics has been cited more than 2200 times, with a significant impact on applications of the theory to the discipline in the past 20 years. A recent paper in JAMS with similar intent, which could serve as a helpful model, focuses on “Resource-Based Theory in Marketing” (Kozlenkova et al. 2014 ). The article dives deeply into a description of the theory and its underlying assumptions, then organizes a systematic review of relevant literature according to various perspectives through which the theory has been applied in marketing. The authors conclude by identifying topical domains in marketing that might benefit from additional applications of the theory (e.g., marketing exchange), as well as related theories that could be integrated meaningfully with insights from the resource-based theory.

Method-based review papers

Method-based review papers review, synthetize, and extend a body of literature that uses the same underlying method. For example, in “Event Study Methodology in the Marketing Literature: An Overview” (Sorescu et al. 2017 ), the authors identify published studies in marketing that use an event study methodology. After a brief review of the theoretical foundations of event studies, they describe in detail the key design considerations associated with this method. The article then provides a roadmap for conducting event studies and compares this approach with a stock market returns analysis. The authors finish with a summary of the strengths and weaknesses of the event study method, which in turn suggests three main areas for further research. Similarly, “Discriminant Validity Testing in Marketing: An Analysis, Causes for Concern, and Proposed Remedies” (Voorhies et al. 2016 ) systematically reviews existing approaches for assessing discriminant validity in marketing contexts, then uses Monte Carlo simulation to determine which tests are most effective.

Our long-term editorial strategy is to make sure JAMS becomes and remains a well-recognized outlet for both meta-analysis and systematic managerial review papers in marketing. Ideally, review papers would come to represent 10%–20% of the papers published by the journal.

Process and structure for review papers

In this section, we review the process and typical structure of a systematic review paper, which lacks any long or established tradition in marketing research. The article by Grewal et al. ( 2018 ) provides a summary of effects-focused review papers (i.e., meta-analyses), so we do not discuss them in detail here.

Systematic literature review process

Some review papers submitted to journals take a “narrative” approach. They discuss current knowledge about a research domain, yet they often are flawed, in that they lack criteria for article inclusion (or, more accurately, article exclusion), fail to discuss the methodology used to evaluate included articles, and avoid critical assessment of the field (Barczak 2017 ). Such reviews tend to be purely descriptive, with little lasting impact.

In contrast, a systematic literature review aims to “comprehensively locate and synthesize research that bears on a particular question, using organized, transparent, and replicable procedures at each step in the process” (Littell et al. 2008 , p. 1). Littell et al. describe six key steps in the systematic review process. The extent to which each step is emphasized varies by paper, but all are important components of the review.

Topic formulation . The author sets out clear objectives for the review and articulates the specific research questions or hypotheses that will be investigated.

Study design . The author specifies relevant problems, populations, constructs, and settings of interest. The aim is to define explicit criteria that can be used to assess whether any particular study should be included in or excluded from the review. Furthermore, it is important to develop a protocol in advance that describes the procedures and methods to be used to evaluate published work.

Sampling . The aim in this third step is to identify all potentially relevant studies, including both published and unpublished research. To this end, the author must first define the sampling unit to be used in the review (e.g., individual, strategic business unit) and then develop an appropriate sampling plan.

Data collection . By retrieving the potentially relevant studies identified in the third step, the author can determine whether each study meets the eligibility requirements set out in the second step. For studies deemed acceptable, the data are extracted from each study and entered into standardized templates. These templates should be based on the protocols established in step 2.

Data analysis . The degree and nature of the analyses used to describe and examine the collected data vary widely by review. Purely descriptive analysis is useful as a starting point but rarely is sufficient on its own. The examination of trends, clusters of ideas, and multivariate relationships among constructs helps flesh out a deeper understanding of the domain. For example, both Hult ( 2015 ) and Huber et al. ( 2014 ) use bibliometric approaches (e.g., examine citation data using multidimensional scaling and cluster analysis techniques) to identify emerging versus declining themes in the broad field of marketing.

Reporting . Three key aspects of this final step are common across systematic reviews. First, the results from the fifth step need to be presented, clearly and compellingly, using narratives, tables, and figures. Second, core results that emerge from the review must be interpreted and discussed by the author. These revelatory insights should reflect a deeper understanding of the topic being investigated, not simply a regurgitation of well-established knowledge. Third, the author needs to describe the implications of these unique insights for both future research and managerial practice.

A new paper by Watson et al. ( 2017 ), “Harnessing Difference: A Capability-Based Framework for Stakeholder Engagement in Environmental Innovation,” provides a good example of a systematic review, starting with a cohesive conceptual framework that helps establish the boundaries of the review while also identifying core constructs and their relationships. The article then explicitly describes the procedures used to search for potentially relevant papers and clearly sets out criteria for study inclusion or exclusion. Next, a detailed discussion of core elements in the framework weaves published research findings into the exposition. The paper ends with a presentation of key implications and suggestions for the next steps. Similarly, “Marketing Survey Research Best Practices: Evidence and Recommendations from a Review of JAMS Articles” (Hulland et al. 2017 ) systematically reviews published marketing studies that use survey techniques, describes recent trends, and suggests best practices. In their review, Hulland et al. examine the entire population of survey papers published in JAMS over a ten-year span, relying on an extensive standardized data template to facilitate their subsequent data analysis.

Structure of systematic review papers

There is no cookie-cutter recipe for the exact structure of a useful systematic review paper; the final structure depends on the authors’ insights and intended points of emphasis. However, several key components are likely integral to a paper’s ability to contribute.

Depth and rigor

Systematic review papers must avoid falling in to two potential “ditches.” The first ditch threatens when the paper fails to demonstrate that a systematic approach was used for selecting articles for inclusion and capturing their insights. If a reader gets the impression that the author has cherry-picked only articles that fit some preset notion or failed to be thorough enough, without including articles that make significant contributions to the field, the paper will be consigned to the proverbial side of the road when it comes to the discipline’s attention.

Authors that fall into the other ditch present a thorough, complete overview that offers only a mind-numbing recitation, without evident organization, synthesis, or critical evaluation. Although comprehensive, such a paper is more of an index than a useful review. The reviewed articles must be grouped in a meaningful way to guide the reader toward a better understanding of the focal phenomenon and provide a foundation for insights about future research directions. Some scholars organize research by scholarly perspectives (e.g., the psychology of privacy, the economics of privacy; Martin and Murphy 2017 ); others classify the chosen articles by objective research aspects (e.g., empirical setting, research design, conceptual frameworks; Cleeren et al. 2017 ). The method of organization chosen must allow the author to capture the complexity of the underlying phenomenon (e.g., including temporal or evolutionary aspects, if relevant).


Processes for the identification and inclusion of research articles should be described in sufficient detail, such that an interested reader could replicate the procedure. The procedures used to analyze chosen articles and extract their empirical findings and/or key takeaways should be described with similar specificity and detail.

We already have noted the potential usefulness of well-done review papers. Some scholars always are new to the field or domain in question, so review papers also need to help them gain foundational knowledge. Key constructs, definitions, assumptions, and theories should be laid out clearly (for which purpose summary tables are extremely helpful). An integrated conceptual model can be useful to organize cited works. Most scholars integrate the knowledge they gain from reading the review paper into their plans for future research, so it is also critical that review papers clearly lay out implications (and specific directions) for research. Ideally, readers will come away from a review article filled with enthusiasm about ways they might contribute to the ongoing development of the field.

Helpful format

Because such a large body of research is being synthesized in most review papers, simply reading through the list of included studies can be exhausting for readers. We cannot overstate the importance of tables and figures in review papers, used in conjunction with meaningful headings and subheadings. Vast literature review tables often are essential, but they must be organized in a way that makes their insights digestible to the reader; in some cases, a sequence of more focused tables may be better than a single, comprehensive table.

In summary, articles that review extant research in a domain (topic, theory, or method) can be incredibly useful to the scientific progress of our field. Whether integrating the insights from extant research through a meta-analysis or synthesizing them through a systematic assessment, the promised benefits are similar. Both formats provide readers with a useful overview of knowledge about the focal phenomenon, as well as insights on key dilemmas and conflicting findings that suggest future research directions. Thus, the editorial team at JAMS encourages scholars to continue to invest the time and effort to construct thoughtful review papers.

Barczak, G. (2017). From the editor: writing a review article. Journal of Product Innovation Management, 34 (2), 120–121.

Article   Google Scholar  

Bem, D. J. (1995). Writing a review article for psychological bulletin. Psychological Bulletin, 118 (2), 172–177.

Bettencourt, L. A., & Houston, M. B. (2001). Assessing the impact of article method type and subject area on citation frequency and reference diversity. Marketing Letters, 12 (4), 327–340.

Cleeren, K., Dekimpe, M. G., & van Heerde, H. J. (2017). Marketing research on product-harm crises: a review, managerial implications. Journal of the Academy of Marketing Science, 45 (5), 593–615.

Grewal, D., Puccinelli, N. M., & Monroe, K. B. (2018). Meta-analysis: error cancels and truth accrues. Journal of the Academy of Marketing Science, 46 (1).

Hanssens, D. M. (2018). The value of empirical generalizations in marketing. Journal of the Academy of Marketing Science, 46 (1).

Huber, J., Kamakura, W., & Mela, C. F. (2014). A topical history of JMR . Journal of Marketing Research, 51 (1), 84–91.

Hulland, J., Baumgartner, H., & Smith, K. M. (2017). Marketing survey research best practices: evidence and recommendations from a review of JAMS articles. Journal of the Academy of Marketing Science. https://doi.org/10.1007/s11747-017-0532-y .

Hult, G. T. M. (2015). JAMS 2010—2015: literature themes and intellectual structure. Journal of the Academy of Marketing Science, 43 (6), 663–669.

Knoll, J., & Matthes, J. (2017). The effectiveness of celebrity endorsements: a meta-analysis. Journal of the Academy of Marketing Science, 45 (1), 55–75.

Kozlenkova, I. V., Samaha, S. A., & Palmatier, R. W. (2014). Resource-based theory in marketing. Journal of the Academy of Marketing Science, 42 (1), 1–21.

Littell, J. H., Corcoran, J., & Pillai, V. (2008). Systematic reviews and meta-analysis . New York: Oxford University Press.

Book   Google Scholar  

Martin, K. D., & Murphy, P. E. (2017). The role of data privacy in marketing. Journal of the Academy of Marketing Science, 45 (2), 135–155.

Rindfleisch, A., & Heide, J. B. (1997). Transaction cost analysis: past, present, and future applications. Journal of Marketing, 61 (4), 30–54.

Sorescu, A., Warren, N. L., & Ertekin, L. (2017). Event study methodology in the marketing literature: an overview. Journal of the Academy of Marketing Science, 45 (2), 186–207.

Verma, V., Sharma, D., & Sheth, J. (2016). Does relationship marketing matter in online retailing? A meta-analytic approach. Journal of the Academy of Marketing Science, 44 (2), 206–217.

Voorhies, C. M., Brady, M. K., Calantone, R., & Ramirez, E. (2016). Discriminant validity testing in marketing: an analysis, causes for concern, and proposed remedies. Journal of the Academy of Marketing Science, 44 (1), 119–134.

Watson, R., Wilson, H. N., Smart, P., & Macdonald, E. K. (2017). Harnessing difference: a capability-based framework for stakeholder engagement in environmental innovation. Journal of Product Innovation Management. https://doi.org/10.1111/jpim.12394 .

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Palmatier, R.W., Houston, M.B. & Hulland, J. Review articles: purpose, process, and structure. J. of the Acad. Mark. Sci. 46 , 1–5 (2018). https://doi.org/10.1007/s11747-017-0563-4

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review article and research article difference

Identifying and Locating Empirical Articles

  • Types of Scholarly Articles

Empirical Articles vs Review Articles

  • Locating Empirical Articles

Empirical articles are written to share the results of original research. Their authors will share their findings, including results, data, and ideas for future research. This will allow other researchers to learn more and conduct further studies.

Review articles are written to compare and discuss the results of multiple articles. They may be structured similarly to original research articles, but they are synthesizing what others have written about, rather than reporting on their own research.

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Know the difference between empirical and review articles.

Empirical article An empirical (research) article reports methods and findings of an original research study conducted by the authors of the article.  

Literature Review article A review article or "literature review" discusses past research studies on a given topic.

Definition of an empirical study:  An empirical research article reports the results of a study that uses data derived from actual observation or experimentation. Empirical research articles are examples of primary research.

Parts of a standard empirical research article:  (articles will not necessary use the exact terms listed below.)

  • Abstract  ... A paragraph length description of what the study includes.
  • Introduction ...Includes a statement of the hypotheses for the research and a review of other research on the topic.
  • Who are participants
  • Design of the study
  • What the participants did
  • What measures were used
  • Results ...Describes the outcomes of the measures of the study.
  • Discussion ...Contains the interpretations and implications of the study.
  • References ...Contains citation information on the material cited in the report. (also called bibliography or works cited)

Characteristics of an Empirical Article:

  • Empirical articles will include charts, graphs, or statistical analysis.
  • Empirical research articles are usually substantial, maybe from 8-30 pages long.
  • There is always a bibliography found at the end of the article.

Type of publications that publish empirical studies:

  • Empirical research articles are published in scholarly or academic journals
  • These journals are also called “peer-reviewed,” or “refereed” publications.

Examples of such publications include:

  • Computers in Human Behavior
  • Journal of Educational Psychology

Examples of databases that contain empirical research:  (selected list only)

  • Web of Science

This page is adapted from the Sociology Research Guide: Identify Empirical Articles page at Cal State Fullerton Pollak Library.

Know the difference between scholarly and non-scholarly articles.

"Scholarly" journal = "Peer-Reviewed" journal = "Refereed" journal

When researching your topic, you may come across many different types of sources and articles. When evaluating these sources, it is important to think about: 

  • Who is the author? 
  • Who is the audience or why was this written? 
  • Where was this published? 
  • Is this relevant to your research? 
  • When was this written? Has it been updated? 
  • Are there any citations? Who do they cite?  

Helpful Links and Guides

Here are helpful links and guides to check out for more information on scholarly sources: 

  • This database contains data on different types of serials and can be used to determine whether a periodical is peer-reviewed or not:  Ulrich's Periodicals Directory  
  • The UC Berkeley Library published this useful guide on evaluating resources, including the differences between scholarly and popular sources, as well as how to find primary sources:  UC Berkeley's Evaluating Resources LibGuide
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Types of journal articles

It is helpful to familiarise yourself with the different types of articles published by journals. Although it may appear there are a large number of types of articles published due to the wide variety of names they are published under, most articles published are one of the following types; Original Research, Review Articles, Short reports or Letters, Case Studies, Methodologies.

Original Research:

This is the most common type of journal manuscript used to publish full reports of data from research. It may be called an  Original Article, Research Article, Research, or just  Article, depending on the journal. The Original Research format is suitable for many different fields and different types of studies. It includes full Introduction, Methods, Results, and Discussion sections.

Short reports or Letters:

These papers communicate brief reports of data from original research that editors believe will be interesting to many researchers, and that will likely stimulate further research in the field. As they are relatively short the format is useful for scientists with results that are time sensitive (for example, those in highly competitive or quickly-changing disciplines). This format often has strict length limits, so some experimental details may not be published until the authors write a full Original Research manuscript. These papers are also sometimes called Brief communications .

Review Articles:

Review Articles provide a comprehensive summary of research on a certain topic, and a perspective on the state of the field and where it is heading. They are often written by leaders in a particular discipline after invitation from the editors of a journal. Reviews are often widely read (for example, by researchers looking for a full introduction to a field) and highly cited. Reviews commonly cite approximately 100 primary research articles.

TIP: If you would like to write a Review but have not been invited by a journal, be sure to check the journal website as some journals to not consider unsolicited Reviews. If the website does not mention whether Reviews are commissioned it is wise to send a pre-submission enquiry letter to the journal editor to propose your Review manuscript before you spend time writing it.  

Case Studies:

These articles report specific instances of interesting phenomena. A goal of Case Studies is to make other researchers aware of the possibility that a specific phenomenon might occur. This type of study is often used in medicine to report the occurrence of previously unknown or emerging pathologies.

Methodologies or Methods

These articles present a new experimental method, test or procedure. The method described may either be completely new, or may offer a better version of an existing method. The article should describe a demonstrable advance on what is currently available.

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Empirical Journal Articles

Empirical Article - (Original Research) Based on experience and observation, rather than systematic logic. (according to MedicineNet.com)

The articles contain original research (such as scientific experiments, surveys and research studies) A list of references or sources is provided at the end of each article An editorial board, composed of experts in the field, reviews articles to decide whether they should be accepted; this is also known as "refereed," "peer-reviewed," "professional," "scholarly", or "academic". Uses a specialized vocabulary for that field.

Below are two websites that explain Empirical articles and research:

Empirical Research: How to Recognize and Locate (Penn State University) - Empirical Research PDF

Review Journal Articles

Review Article

An article that summarizes the progress or current state in some particular subject, area, or topic.

How to write a "Review Article?" (National Library of Medicine) - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548566/

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  • Sep 14, 2021

What's the difference between a research article and a review article-The hidden secrets?

Are you getting more confused on what is review article and research article and what are their major differences? Here we have provided a clear idea to make you feel understand in a better way. Let’s see each one of the them more in detail.

What is a research article?

The research articles, occasionally termed to as primary sources or empirical paper which rely on original research report. They consist of the sections namely abstract, introduction, literature review, research methodology, results & discussion and conclusion. Primary or Empirical research studies report original research, highlighting the diverse steps involved in the research process.

The structure of an empirical paper is explained in detail as under:

Abstract : The abstract is the first and foremost section of the empirical paper and the content should be well written in a precise manner. The following key points are important for abstract formulation

It delivers a description of the research problem being examined

includes the contributors and relevant characteristics of those contributors

defines the research methodology of the study

précises the basic findings of the research study

contains the implications or applications and conclusions of the research study's findings.

Introduction: Traces the way the research problem that is being studied has developed and provides the determination for the examination.

Research Methodology : Specifies how the examination was conducted; what measures were used.

Results : intelligences the findings and analyses of the research study

Discussion : summarizes, infers and discusses the implications of the examination results

Conclusion : Concludes the research study and its outcomes in a precise manner.

What is a review article ?

The review article is also sometimes called as survey article or literature reviews or secondary sources , synthesize or analyze research previously conducted in primary sources. The review articles usually summarize the current state of research on a given research topic.

The review articles critically evaluate the previously published research articles. The organization, combination of the previously published material, and evaluation of this material provide an understanding of the progress of research in clarifying a research problem. The Literature reviews provides the following key points:

gives a clear definition and explanation of the research problem

provides a summary of earlier research to inform the reader of what the research status is

identifies relationships, contradictions, problem gaps and discrepancies in the material

makes suggestions in the upcoming step to solve the problem.

The structure of a review paper is detailed as under:

Abstract: Notifies about the main objectives and result of each review article taken for development

Introduction: Provides information about the background, specifies the motivation for the review, describes the focus, the research question and describes the text structure.

Detailed literature survey and frame a Comparative table: In this section, we need to summarize each referred article in terms of author(s) name, year of publication, findings of the particular research article, advantages and limitations of the study

Future scope of the work (if applicable)

Below table gives you a clear understanding of the major difference between a review and a research article.

review article and research article difference

Hope this article is useful for the research aspirants and the scholars who are planning to publish their articles in journal

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Descriptions of Types of Reviews

Reproduced from: Grant MJ, Booth A. A typology of reviews: an analysis of 14 review types and associated methodologies .  Health Info Libr J . 2009 Jun;26(2):91-108. doi: 10.1111/j.1471-1842.2009.00848.x. Review. PubMed PMID: 19490148.

Further Reading

Sutton A, Clowes M, Preston L, Booth A. Meeting the review family: exploring review types and associated information retrieval requirements . Health Info Libr J. 2019;36(3):202-222. doi: 10.1111/hir.12276.

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  • Published: 01 June 2024

Effective dosage and mode of exercise for enhancing cognitive function in Alzheimer's disease and dementia: a systematic review and Bayesian Model-Based Network Meta-analysis of RCTs

  • Yuan Yuan 1 ,
  • Yong Yang 2 ,
  • XiaoFei Hu 3 ,
  • Lin Zhang 4 ,
  • Zhiyu Xiong 5 ,
  • Ying Bai 1 ,
  • JiaLe Zeng 6 &
  • Feng Xu 7  

BMC Geriatrics volume  24 , Article number:  480 ( 2024 ) Cite this article

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Research the dose–response relationship between overall and certain types of exercise and cognitive function in older adults with Alzheimer's disease and dementia.

Systemic and Bayesian Model-Based Network Meta-Analysis.

In our study, we analyzed data from randomized controlled trials investigating the effects of different exercises on cognitive outcomes in older adults with AD. We searched the Web of Science, PubMed, Cochrane Central Register of Controlled Trials, and Embase up to November 2023. Using the Cochrane Risk of Bias tool (Rob2) for quality assessment and R software with the MBNMA package for data analysis, we determined standard mean differences (SMDs) and 95% confidence intervals (95%CrI) to evaluate exercise's impact on cognitive function in AD.

Twenty-seven studies with 2,242 AD patients revealed a nonlinear relationship between exercise and cognitive improvement in AD patients. We observed significant cognitive enhancements at an effective exercise dose of up to 1000 METs-min/week (SMDs: 0.535, SD: 0.269, 95% CrI: 0.023 to 1.092). The optimal dose was found to be 650 METs-min/week (SMDs: 0.691, SD: 0.169, 95% CrI: 0.373 to 1.039), with AE (Aerobic exercise) being particularly effective. For AE, the optimal cognitive enhancement dose was determined to be 660 METs-min/week (SMDs: 0.909, SD: 0.219, 95% CrI: 0.495 to 1.362).

Nonlinear dose–response relationship between exercise and cognitive improvement in Alzheimer’s disease, with the optimal AE dose identified at 660 METs-min/week for enhancing cognitive function in AD.

Peer Review reports


According to a recent report in 2023, the number of people with Alzheimer's in the United States alone has skyrocketed to 6.75 million and is projected to exceed 13.8 million by 2026 [ 1 ]. Alzheimer's dementia has become one of the prominent public health challenges of the twenty-first century [ 2 ]. At the same time, the enormous cost of Alzheimer's disease and dementia(AD) puts a huge strain on society and families, with studies showing that [ 3 ]: According to estimates made in 2019, the global annual societal cost of dementia was US $ 131.34 billion for 55.2 million people living with dementia. This equates to a cost of US $ 23,796 per person with dementia. Out of this amount, direct medical costs amounted to US $ 213.2 billion (16%), direct social sector costs (including long-term care) to US $ 448.7 billion (34%), and informal care costs to US $ 651.4 billion (50%). Moreover, in low- and middle-income countries, family caregivers of people with dementia face high levels of caregiving stress, adverse health effects of long-term care, and difficulties in managing the caregiving process. They also struggle to adapt to life changes and meet their own needs [ 4 ].

In the previous study, a comprehensive meta-analysis synthesizing findings from 43 prospective observational studies and 153 randomized controlled trials, Yu et al. established exercise as an effective intervention for preventing AD in older adults [ 5 ]. This conclusion is supported by similarities between animal models and human AD, including amyloid-beta deposition and tau protein pathology. Animal studies have further validated exercise's molecular basis for cognitive enhancement in AD, demonstrating its impact on reducing beta-amyloid deposition and improving cerebrovascular function [ 6 , 7 ]. Additionally, a recent study by Holstein et al. in 'Nature Neuroscience' highlighted that exercise enhances brain health by increasing blood flow and promoting the circulation of cerebrospinal fluid [ 8 ]. Collectively, these findings underscore the role of regular exercise in boosting neurotrophic factor expression, exerting anti-inflammatory effects, and improving cognitive function and neuroplasticity.

However, different exercises have different effects on improving cognition in AD. Susana et. al. of the meta-analysis showed that aerobic exercise seems to significantly improve AD patients’ cognition [ 9 ]. Although studies have proven that aerobic exercise can improve the cognitive function of AD patients, the results of the network meta-analysis study by Shi et.al showed that resistance exercise was the most effective way to improve the cognitive function of AD patients [ 10 ]. In previous dose–response meta-analyses, the effects associated with resistance exercise on healthy older adults had yielded good insights [ 11 , 12 ]. Additionally, the dose and response network meta of Daniel et. al. opened a new direction in the study of dose–response relationships and confirmed for the first time that the relationship between exercise dose and cognition in older adults was nonlinear and found older adults can achieve clinically meaningful benefits at doses lower than the WHO (724 METs-min per week) [ 13 ]. The varying effectiveness of exercise interventions on cognitive function in AD patients may largely be due to differences in exercise dosages. Previous dose–response studies often treated exercises within the same category as equivalent, regardless of their duration (e.g., equating a 40-min session with a 100-min session). Such an approach may overlook the distinct advantages of specific exercise types. For instance, it might ignore the benefits of strength training on bone density and metabolic rate or the cardiovascular benefits inherent to aerobic exercise [ 12 , 14 , 15 , 16 ]. Moreover, the reliance on single-category dose–response modeling has made it challenging to accurately model the effects of different interventions. Additionally, while much of the existing research has focused on mild cognitive impairment a precursor to AD there has been a significant gap in studies specifically exploring the optimal exercise dosage and its impact on cognitive function in AD patients. Our study aims to fill this gap by providing nuanced insights into how different exercise doses can uniquely contribute to health outcomes in AD patients, representing a vital advancement in the field.

In order to fill the gap, our study follows the method used by Daniel et. al. to evaluate exercise intensity using task metabolic equivalents [ 13 ]. By utilizing a new dose–response model of network meta-analysis through a classical Bayesian prior theory model in probability [ 17 , 18 ]. Our research meticulously evaluates existing randomized controlled trials on exercise interventions designed to enhance cognitive functions in AD. It delves into the nuanced, non-linear dynamics between the intensity and volume of exercise and the observed cognitive benefits. The study's core objective is to pinpoint the most effective exercise modalities for AD patients, alongside determining the optimal dosage for maximum cognitive improvement. This investigation is poised to substantially enrich evidence-based guidelines for exercise in managing cognitive symptoms of AD, thereby equipping healthcare professionals with robust data to inform their clinical decisions.

Search strategy

This systematic review and network meta-analysis is registered on the international Prospective Register of Systematic Reviews site as CRD 42023484877, and it was reported following the PRISMA checklist [ 19 ]. We conducted a comprehensive literature search across Web of Science, PubMed, Cochrane Central Register of Controlled Trials, and Embase databases up to November 2023. To ensure the search was both thorough and precise, we crafted a strategy using medical subject headings (MeSH) and keyword searches specifically in PubMed, with three authors reviewing for accuracy and completeness. Our search utilized a combination of MeSH terms and synonyms including "Alzheimer”," "Dementia," "Aged," "Older adults," "Aging," "Cognitive impairment," and terms related to exercise such as "Physical Activity," "Exercise," "Training," "Resistance Exercise," and "Aerobic Exercise." We explicitly excluded studies on Mild Cognitive Impairment (MCI) using the term "NOT (MCI, Mild Cognitive Impairment) ." Detailed search strategies, including the specific terms, dates, and methodologies employed, are documented in Appendix File 1 .

Study selection

We first imported the literature we retrieved into the Endnote 20 software (Clarivate Analytics, Philadelphia, PA, USA) to screen for duplicate articles. We also manually screened for duplicates. Secondly, we excluded animal experiments, conference abstracts, experimental protocols, guidelines, and reports, as well as non-English literature. Finally, we meticulously screened for and excluded reviews and meta-analyses to guarantee that our study exclusively incorporated RCTs. Title/abstract and full-text screening were conducted independently and in duplicate by two investigators (Y.Y/X.F.H) , with disagreements resolved by discussion or adjudication by a third author (Yang. Y) .

Eligibility criteria

Types of participants.

Participants must be diagnosed with AD and meet age criteria for older adults 65 years and older. Secondly, only studies focusing on cognitive impairment in healthy older adults and subjects clinically diagnosed with Mild cognitive impairment (MCI) were excluded. Furthermore, we also excluded studies of cognitive impairment due to other diseases (e.g. Parkinson's, stroke, diabetes, Attention Deficit/Hyperactivity Disorder, Epilepsy, Multiple Sclerosis, Autism, or Schizophrenia, etc.) and to ensure completely that the study looked at populations with AD.

Types of intervention

Previous research exercises had focused on increasing planned, structured activities. However, activities like gardening, daily tasks, household chores, and others with low task metabolic equivalents (METs, used to assess the intensity of exercise) do not result in muscle contraction sufficient to increase the body's calorie demand significantly. Therefore, it is challenging to make reasonable recommendations regarding appropriate exercise doses for AD [ 20 ].

In our study, both the intervention and control groups engaged in some form of physical activity. However, to be included in our intervention analysis, studies needed to specify the duration, frequency, and methods of exercise, quantifiable in METs. This research focused exclusively on the impact of exercise on cognitive impairment in AD, omitting studies that incorporated other interventions such as exercise combined with cognitive therapy, gardening, music therapy, or physiotherapy. This exclusion criterion was essential to isolate the cognitive benefits attributable solely to physical exercise. Moreover, the control group received standard care, including daily living guidance and health education, without additional exercise or specific health interventions. A comprehensive definition of the exercise interventions analyzed is available in Appendix File 9 .

Types of outcome measures

In our studies, experiments that reported at least one outcome with one of the global cognitive measures were eligible for inclusion. (ex: MMSE [ 21 ], ADAS-Cog [ 22 ], MoCA [ 23 ]).

Types of studies

In order to keep the risk of bias at a low to moderate level, both published and unpublished randomized controlled trials (RCTs) were included in our study, whereas non-randomized controlled studies (cohort studies, pathology-control, cross-sectional studies, etc .) were excluded.

Data extraction3

The data from studies that met the inclusion criteria (Y.Y/X.F.H) were extracted independently by two authors and disagreements were resolved by consensus among the third authors (Yang. Y). For each inclusion study, pertinent data and populated into an Excel spreadsheet. the researcher's name, published year of study, sample size (total/male/female), sex, age, intervention and control description, intervention period/frequency/minutes, cognitive assessment tool, and used transformation formulas for estimating the mean and standard deviation (Appendix file 2) any data that could be used to calculate effect size was extracted (Appendix file 3) . The formulas utilized for the calculation of Mean change and SD values were:

According to the guidelines of the Cochrane Handbook, the correlation coefficient ( Corr ) was set to 0.5 [ 24 ]. In addition to meeting the data analysis requirements of the Dose–Response network meta-analysis Package in R, we converted the standard errors ( SE ). n as sample size [ 25 ].

In cases where the required data for dose–response meta-analyses could not be retrieved from published reports, we contacted the authors and requested additional data. In two studies, the authors were able to provide the required data after being contacted [ 26 , 27 ].

Data setting

First, the interventions were coded in two categories; Category I: the intervention and control groups were coded as "Exercise (PA)" and "Control (CON)". Exercise will be viewed as an overall equivalent (e.g., regardless of aerobic, anaerobic, exercise, etc.), with the aim of analyzing the optimal dose of overall exercise for AD patients. Category II: Interventions will be coded according to their primary form of PA: “Aerobic exercise” (AE), “Mixed exercise” (MIX), "Tai Chi” (TC), “Resistance training” (RT), “Exergame” (EX) and “control” (CON). The aim was to analyze the optimal dose and optimal modality of the different forms of exercise. At the same time, we chose metabolic equivalents of tasks (METs) to define exercise-specific energy expenditure [ 28 ]. Because METs provide a standardized way to quantify the intensity of different exercises. By measuring energy expenditure in terms of METs, the intensity of various sports and physical activities can be objectively compared, regardless of the type of activity or the individual performing the activity [ 29 ]. Not only, by calculating METs-min consumed per week, our study took into account not only the duration and frequency of exercise (METs-min/week  =  duration minute  ×  times-pre week  ×  MET value) but also the intensity of exercise, which is critical to assess its impact on health outcomes [ 20 , 30 , 31 ]. Additionally, in order to facilitate the connectivity required for Network Meta-analysis, the intervention intensity was classified into five different groups with weekly controls set at 0,250, 500, 750,1000, and 1250 METs-min and it’s proved in the previous study [ 32 , 33 ].

Data synthesis

All data analysis was performed in R version 4.0.3 [ 34 ]. We used the "MBNMAdose" package to analyze the reticulation dose–response relationship which exercise dose and AD cognition impairment [ 17 , 35 ]. We used the Emax functional model, restricted cubic spline, non-parametric model, exponential model different fitting metrics for random and fixed effects models to select the best-fitting model for analyzing our study data. such as DIC (deviation information criterion) , standard deviation, parameters in the model, and residuals [ 36 ]. With the results (Appendix File 5 Table 2) , the restricted cubic spline model of the random effects model was found to have a better fit. Therefore, in our study, we opted restricted cubic spline of the random effects model [ 18 , 37 , 38 ]. In addition, to visualize the best functional model fit to our data, we plotted relative line and box plots of the deviation of equivalent exercises from different exercises in Appendix File 5.

At the same time, we checked the data for three key hypotheses of network meta-analysis network connectivity, consistency (Appendix Table 1) . , and transitivity (Appendix 4: Figure, 4) [ 37 , 39 , 40 ]. Additionally, because included studies assessed cognitive function using different measurement scales, effect measures were pooled as standardized mean differences (SMDs), SMDs do not rely on the specific units of the original scale and therefore can be used to combine results from studies that use different measurement units and ranges, eliminating interpretation barriers that may arise when using raw score differences directly, meanwhile with 95% credible intervals (95% CrI) to assess the credibility of our estimates [ 41 , 42 ].

In order to estimate the overall and different exercise doses that resulted in the predicted maximum significant effect referred to as the ‘optimal exercise dose’. We summarized the result of the dose–response relationship by the MCMC model (Markov Chain Monte Carlo Iterations) [3 chains, 20,000 iterations each (first 10,000 discarded), n. thin = 10] of the beta coefficients on the restricted cubic spline curves by “rjags” package in R [ 43 ]. We positioned the three nodes at the 10th, 50th, and 90th percentile of the exercise dose to visualize our model-fitting results. The code to reproduce the results presented in this paper can be accessed at the first author's e-mail address.

Risk of bias and quality of evidence

Our study was selected according to the Cochrane (Rob2) criteria [ 44 , 45 , 46 ]. and packages “robvis” was used to plot the results in R. Three reviewers (Y.Y/X.F.H/Yang. Y) assessed the study, we assessed only five categories of risk of bias, including randomized sequence generation, bias due to deviation from the intended intervention, incomplete data, bias in measurements, and selective bias in reporting results. Disagreements were resolved by the third author. Additionally, we performed sensitivity analyses and excluded high-risk bias studies to determine the robustness of the overall exercise dose–response model [ 47 ] (Appendix File 8) .

Description of included studies

A total of 1962 potentially eligible studies were searched. After removing literature that did not fit my study by title, abstract, etc., we considered 147 studies that were potentially eligible for inclusion and retrieved full-text articles. After deleting duplicates and applying the inclusion criteria, there were 27 RCT studies [ 26 , 27 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ] included in this analysis were published between 2006 and 2023 (Fig.  1 ) . Out of the total of 2242 participants, 1210 (54%) were male and 1032 (46%) were female. All patients included in the studies had AD and were aged between 65 and 85 years old. In these studies, the exercise interventions in the 17 studies have AE, 8 studies have Mixed, 3 studies have RT, 3 studies have Taiichi and 2 studies were game-based exercise interventions and we provided Characteristics information for the included study in Table  1 . More information about the characteristics of the included studies can be found in Appendix File 3 .

figure 1

PRISMA Flow diagram of the search process for studies. RCT randomized controlled trials

Network connectivity

Whether connectivity is met determines the basis of NMA. Lack of connectivity can lead to low statistical power and misleading results when direct comparison is not possible [ 73 ]. The analysis confirmed no connectivity deficit in the two networks, ensuring the accuracy of the results (Figs.  2 and 3 ).

figure 2

Treatment level. The first value indicates the specific intervention AE Aerobic Exercise, CON Control group, MT Multicomponent Exercise Program, RT Resistance Training, TC: Taichi, EX Exergame exercise

figure 3

Agent-level network plot. the value indicates the corresponding dose of that intervention. AE Aerobic Exercise, CON Control group, MT Multicomponent Exercise Program, RT Resistance Training, TC: Taichi, EX Exergame exercise

Dose–response relationship

Figure  4 shows there was a nonlinear dose–response relationship between overall exercise dose and cognition up to 1000 METs -min/week (SMDs: 0.535, SD: 0.269, 95%Crl: 0.023 to 1.092), with overall exercise showing a significant increase in cognitive function. Above 1000 METs-min/week, the response to cognitive function was significantly diminished. Meanwhile, the optimal dose of overall exercise was estimated at 650 METs-min/week (SMDs:0.691, SD:0.169, 95%Crl: 0.373 to 1.039) for improving cognitive function with AD.

figure 4

Dose–response association between overall exercise dose and change in cognitive function in AD, the exercise dose distribution is represented by the green part in our study. The red part indicates the WHO-recommended exercise dose range. PA overall exercise

In Fig.  5 , we show the dose–response curves for different types of exercise. Surprisingly, AE, EG, and MIX of maximum dose exceed 1000METs-min/week, however, EG did not appear to be effective in improving cognitive function in AD within the dose range. At the same time, we found an inverted U-shaped relationship between exercise dose and cognition function for AE. The optimal AE dose was found at 660 METs -min/week (SMDs: 0.909, SD:0.219, 95% CrI: 0.495 to 1.362). The improvement of cognition effect was not significant for AE at over 980 METs-min/week (SMDs: 0.729, SD: 0.374, 95%CrI: 0.004 to 1.501). On the other hand, mixed exercise was estimated to be effective at improving cognitive function at a small dose level until 180 METs-min/week (SMDs: 0.324, SD: 0.171, 95%Crl: 0.004 to 0.683). It is worth exploring that RT and TC have not found any dose to improve cognitive function in AD.

figure 5

Dose–response association between different exercise doses and change in cognitive function in AD. AE Aerobic Exercise, CON Control group, MT Multicomponent Exercise Program, RT Resistance Training, TC: Taichi, EX Exergame exercise

Risk of bias and certainty of evidence

Thirteen studies had a low risk of bias, 11 studies had a moderate risk of bias, and 4 studies had a high risk of bias (Fig.  6 ). Study-level risk of bias assessments are presented in Appendix File 7. Sensitivity analyses that included only studies with a low risk of bias were consistent with the results of the main analysis (Appendix File 7). The overall quality of the evidence was moderate according to the GRADE system. After excluding studies at high risk of bias (Appendix File 8). The optimal dose of the overall exercise was estimated at 760METs-min/week (SMDs: 0.7663, SD: 0.298, 95%CrI: 0.205 to 1.392) in improving cognitive function. The significance of improving cognitive deficits in AD was not significant at above 880METs-week (SMDs: 0.753, SD: 0.3653, 95%CrI: 0.0535 to 1.526).

figure 6

Cochrane Risk of Tool

Main findings

Our study is the first to explore the nonlinear relationship between exercise dosage and cognitive function in AD, revealing that exercise positively influences cognitive impairment in AD patients. This systematic review and network meta-analysis encompassed 27 randomized controlled trials, involving 2,242 AD patients. Our findings indicate that aerobic, mixed exercise significantly enhances cognitive functions in AD patients. and that the optimal dose of overall exercise to improve cognitive dysfunction in elderly patients with AD was 650 METs-min/week. This also corresponds to approximately 150 min of moderate-intensity exercise per week or 75 min of vigorous exercises per week. This result could provide a theoretical basis for future pairs of clinical trials and indirectly demonstrate the clinical feasibility implications of our study [ 74 ]. In the analysis of the results of different exercise modalities to improve cognitive deficits in AD patients, it was concluded that 660 METs -min/week of aerobic exercise was the optimal dose to improve cognitive function in AD, which is consistent with the results of previous Susana et. al. study [ 9 ]. Our study expands upon the research conducted by Susana et al., offering a detailed exploration into the optimal dosage of specific exercise intensities for enhancing cognitive function in AD patients. This investigation delves further into the empirical validity of the findings, aiming to refine and substantiate the recommended exercise protocols for AD patients.

There are several key strengths to our study. First, our study's use of metabolic equivalents of task (METs) to assess exercise intensity lies in its simplicity, versatility, and ability to easily compare different activities. METs are relative values of resting metabolic rate, allowing use by people across age, gender, and culture, facilitating the formulation of public health guidelines and public understanding. In addition, METs can quantitatively compare various activity intensities, supporting individuals and health professionals in developing and adjusting exercise plans [ 28 ]. Second, our study included a relatively large sample size of AD, and in order to achieve the study aim, our study provided adequate statistical power. Third, we applied the current state of the newest meta-analytical techniques to investigate the dose–response between exercise and the improvement of cognition function in AD. The new method allowed us to determine the effective dose of exercise and the optimal dose of different modalities for cognitive improvement in AD patients. Also, order to WHO recommendations, exercise improves cognitive function in patients with AD, and indirectly proves any level of exercise is better than no exercise [ 74 , 75 ]. Our research results not only determined that exercise within the effective dose range is 1000 METs-min/week but also identified 650 METs-min/week as the optimal dose to improve cognitive function in AD. The actual recommendations of the WHO (600 ~ 1200METs-min/week) are echoed, and we have confirmed the effectiveness of the WHO through the existing evidence and helped medical staff better understand the strength of the WHO recommendations. Fourth, our study utilizes direct, indirect, and network estimation methods to compare the relative efficacy of various exercise interventions. This comprehensive approach enabled us to identify exercise as the most effective intervention for enhancing cognitive function in AD. We found that all types of exercise evaluated are associated with improvements in overall cognition. However, aerobic exercise has a more significant interaction with overall cognition than other types of exercise. Comparison to previous studies reporting that resistance exercise improves overall cognition in dementia or MCI populations [ 13 , 76 ], The results of our study indicated that only aerobic exercise was effective in improving cognitive function in patients with AD. This was due to the strict control of inclusion and exclusion criteria, which focused specifically on AD. On the other hand, the study found a weaker dose response of mixed exercise with resistance training to improve cognitive function in patients with AD. This may be the reason why there are too few randomized controlled trials for relevant AD and more randomized controlled trials for AD patients are expected in the future, seeking to prove the effectiveness of mixed exercise versus resistance exercise on cognition in AD.


There are several limitations in our study. Firstly, we were unable to conduct a more in-depth statistical analysis of heterogeneity due to the small number of included studies. Instead, we used a risk assessment tool to assess bias. Secondly, we did not thoroughly analyze some potential covariates such as education level, gender, and weight of the elderly, which could contribute to heterogeneity in the study results. Thirdly, we categorized the methods of evaluating cognitive impairment in AD patients into global cognitive impairment evaluation (primarily using scale evaluation) and executive cognitive impairment evaluation methods (assessing working memory, switching, and inhibition). Our primary outcome focused on the global cognitive impairment scale evaluation. Although our study identifying optimal exercise doses for AD patients provides an evidence-based recommendation aimed at promoting cognitive health, its applicability may vary due to global cognitive impairment and executive cognition. Functional impairment varies with different types of cognitive impairment. Individual differences, such as the patient's performance level, disease stage, and specific type of cognitive impairment, all need to be considered to ensure the effectiveness and safety of the exercise program. Therefore, although 650 METs-min/week provides a useful starting point, individualized adjustment of exercise dose and a combination of multimodal interventions may better meet the individual needs of AD patients, thereby maximizing positive effects on cognition and function. Fourth, our study only included English language literature, potentially leading to missing data from researchers in other countries and limiting the generalizability of our results.

Lastly, although metabolic equivalents of exercise (METs) are a widely used metric for assessing exercise intensity, which quantifies the intensity of different exercises in terms of their ratio relative to resting-state energy expenditure, in practice, the application of METs faces several significant limitations [ 77 ]. First, the calculation of METs is based on the average resting metabolic rate, without considering individual differences that affect energy expenditure, such as age, gender, weight, and physical condition. This means that the same activity may represent different actual intensities for different individuals. Second, MET values provide a fixed estimate of energy expenditure for an activity but lack the sensitivity to capture subtle changes in activity intensity, especially when distinguishing between high- and low-intensity exercise. In addition, the resting metabolic rate of all individuals is assumed to be a uniform standard (1 MET), ignoring the actual differences in energy expenditure in the resting state between people. METs are also difficult to accurately assess complex exercises or contain multiple levels of intensity, and to accurately measure exercise intensity in everyday settings where specialized measurement equipment is not available. Finally, standard MET values do not apply to individuals with specific health conditions because it does not reflect the unique responses of these individuals to exercises. Therefore, while METs provide a convenient metric for rapid estimation of exercise intensity, to obtain a more accurate and personalized assessment, other methods including heart rate monitoring are recommended, taking into account the individual's specific health status and energy expenditure characteristics.

Clinical implications and directions for future research

Our study not only corroborates previous findings on the efficacy of aerobic exercise in enhancing cognitive function in AD patients but also found a specific dose–response relationship, identifying an optimal aerobic exercise dose of 660 METs-min/week [ 9 ]. Furthermore, we established that the overall exercise dose aligns with the World Health Organization's recommended range. By pinpointing effective modalities and dosages for cognitive improvement in AD patients, our research paves the way for future exercise guidelines. In addition, implementing exercise interventions for AD patients presents significant logistical challenges. Effective execution of aerobic exercise programs demands skilled supervision and considerable resources. Comprehensive planning is essential, incorporating policy development, economic considerations, and future research directions [ 78 ]. Both government bodies and the private sector must invest in public health policies and infrastructure. This investment should focus on creating safe and accessible exercise venues, alongside professional and public education initiatives to heighten awareness of AD and the advantages of regular exercise. Concurrently, conducting cost-effectiveness analyses can highlight the potential of exercise interventions to reduce the long-term financial burden of AD care. Additionally, financial policies and incentives aimed at promoting investments in exercise programs for the prevention and management of AD are crucial. This multifaceted approach is key to enhancing the feasibility and success of exercise interventions in the AD patient population, ultimately contributing to improved health outcomes and reduced societal costs.

Our study incorporates the latest Bayesian modeling 'MBNMAdose' package to determine the dose–response relationship between different types of exercise and cognitive function in patients with AD. We found that the optimal overall exercise and AE dose. Using these findings, scientifically prescribed exercise can help us better cope with the cognitive function of AD by developing appropriate exercise prescription guidelines. Furthermore, given the limitations of the previously explained meta-analyses and the insufficient number of studies in the existing literature, it is important to interpret the results with caution. In the future, more detailed randomized controlled trials using a randomized group approach with different exercise doses are recommended to obtain more direct evidence on the relative effectiveness of exercise dose and response in different exercise interventions. In addition, the baseline physical tolerances of different AD patients should be fully considered to develop a rational exercise prescription programmer.

Availability of data and materials

If reviewers want to repeat the results of our study data, Please contact the first author by e-mail.


Randomized controlled trials

Alzheimer's disease and dementia

Standardized Mean Difference

Standard Deviation

95% Credible Interval

Aerobic exercise

Mixed exercise

Resistance training

Exergame exercise

Control group

2023 Alzheimer’s disease facts and figures. Alzheimers & Dementia. 2023;19(4):1598–695.

Article   Google Scholar  

Frankish H, Horton R. Prevention and management of dementia: a priority for public health. Lancet. 2017;390(10113):2614–5.

Article   PubMed   Google Scholar  

Wimo A, Seeher K, Cataldi R, Cyhlarova E, Dielemann JL, Frisell O, Guerchet M, Jönsson L, Malaha AK, Nichols E, et al. The worldwide costs of dementia in 2019. Alzheimers & Dementia. 2023;19(7):2865–73.

Kılıç B, Hiçdurmaz D, Ayhan Y, Saka E. Perspectives of Family Caregivers of People With Alzheimer's Disease on Caregiving Experience and Needs: A Qualitative Study. J Psychosoc Nurs Ment Health Serv. 2023;61:1–10.

Yu JT, Xu W, Tan CC, Andrieu S, Suckling J, Evangelou E, Pan A, Zhang C, Jia J, Feng L, et al. Evidence-based prevention of Alzheimer’s disease: systematic review and meta-analysis of 243 observational prospective studies and 153 randomised controlled trials. J Neurol Neurosurg Psychiatry. 2020;91(11):1201–9.

Norevik CS, Huuha AM, Røsbjørgen RN, Bergersen LH, Jacobsen K, Miguel-dos-Santos R, Tari AR. Exercised blood plasma promotes hippocampal neurogenesis in the Alzheimer's disease rat brain. J Sport Health Sci. 2024;13(2):245–55.

Tari AR, Nauman J, Zisko N, Skjellegrind HK, Bosnes I, Bergh S, Stensvold D, Selbæk G, Wisløff U. Temporal changes in cardiorespiratory fitness and risk of dementia incidence and mortality: a population-based prospective cohort study. The Lancet Public Health. 2019;4(11):e565–74.

Holstein-Ronsbo S, Gan YM, Giannetto MJ, Rasmussen MK, Sigurdsson B, Beinlich FRM, Rose L, Untiet V, Hablitz LM, Kelley DH, et al. Glymphatic influx and clearance are accelerated by neurovascular coupling. Nat Neurosci. 2023;26(6):1042–53.

Article   PubMed   PubMed Central   Google Scholar  

Lopez-Ortiz S, Valenzuela PL, Seisdedos MM, Morales JS, Vega T, Castillo-Garcia A, Nisticò R, Mercuri NB, Lista S, Lucia A. Exercise interventions in Alzheimer’s disease: A systematic review and meta-analysis of randomized controlled trials. Ageing Res Rev. 2021;72:101479.

Lv S, Wang Q, Liu W, Zhang X, Cui M, Li X, Xu Y. Comparison of various exercise interventions on cognitive function in Alzheimer’s patients: A network meta-analysis. Arch Gerontol Geriatr. 2023;115:105113.

Nicola F, Catherine S. Dose–response relationship of resistance training in older adults: a meta-analysis. Br J Sports Med. 2011;45(3):233–4.

Borde R, Hortobágyi T, Granacher U. Dose–response relationships of resistance training in healthy old adults: a systematic review and meta-analysis. Sports Med. 2015;45:1693–720.

Gallardo-Gómez D, del Pozo-Cruz J, Noetel M, Álvarez-Barbosa F, Alfonso-Rosa RM, del Pozo CB. Optimal dose and type of exercise to improve cognitive function in older adults: A systematic review and bayesian model-based network meta-analysis of RCTs. Ageing Res Rev. 2022;76:101591.

Chen ML, Wotiz SB, Banks SM, Connors SA, Shi Y. Dose-Response Association of Tai Chi and Cognition among Community-Dwelling Older Adults: A Systematic Review and Meta-Analysis. Int J Environ Res Public Health. 2021;18(6):3179.

Sanders LMJ, Hortobágyi T, la Bastide-van GS, van der Zee EA, van Heuvelen MJG. Dose-response relationship between exercise and cognitive function in older adults with and without cognitive impairment: A systematic review and meta-analysis. PLoS ONE. 2019;14(1):e0210036.

Article   CAS   PubMed   PubMed Central   Google Scholar  

Shao Z, Hu M, Zhang D, Zeng X, Shu X, Wu X, Kwok TCY, Feng H. Dose-response relationship in non-pharmacological interventions for individuals with mild cognitive impairment: A systematic review and meta-analysis of randomised controlled trials. J Clin Nurs. 2022;31(23–24):3390–401.

Pedder H. MBNMAdose: An R package for incorporating dose-response information into Network Meta-Analysis. In: Evidence Synthesis and Meta-Analysis in R Conference. 2021: 2021.

Mawdsley D, Bennetts M, Dias S, Boucher M, Welton NJ. Model-based network meta-analysis: a framework for evidence synthesis of clinical trial data. CPT: Pharmacometrics syst pharmacol. 2016;5(8):393–401.

CAS   PubMed   Google Scholar  

Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, Shamseer L, Tetzlaff JM, Akl EA, Brennan SE. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. Int J Surg. 2021;88:105906.

Ainsworth BE, Haskell WL, Herrmann SD, Meckes N, Bassett DR Jr, Tudor-Locke C, Greer JL, Vezina J, Whitt-Glover MC, Leon AS. 2011 Compendium of Physical Activities: a second update of codes and MET values. Med Sci Sports Exerc. 2011;43(8):1575–81.

Arevalo-Rodriguez I, Smailagic N. i Figuls MR, Ciapponi A, Sanchez-Perez E, Giannakou A, Pedraza OL, Cosp XB, Cullum S: Mini-Mental State Examination (MMSE) for the detection of Alzheimer’s disease and other dementias in people with mild cognitive impairment (MCI). Cochrane Database Syst Rev. 2015;3:CD010783.

Google Scholar  

Cano SJ, Posner HB, Moline ML, Hurt SW, Swartz J, Hsu T, Hobart JC. The ADAS-cog in Alzheimer’s disease clinical trials: psychometric evaluation of the sum and its parts. J Neurol Neurosurg Psychiatry. 2010;81(12):1363–8.

Hobson J. The montreal cognitive assessment (MoCA). Occup Med. 2015;65(9):764–5.

Higgins JP, Green S. Cochrane handbook for systematic reviews of interventions. 2008.

Book   Google Scholar  

Watt JA, Del Giovane C, Jackson D, Turner RM, Tricco AC, Mavridis D, Straus SE, Veroniki A-A. Incorporating dose effects in network bmj. 2022;376:e067003.

PubMed   Google Scholar  

Angiolillo A, Leccese D, Ciccotelli S, Di Cesare G, D’Elia K, Aurisano N, Matrone C, Dentizzi C, Di Costanzo A. Effects of Nordic walking in Alzheimer’s disease: A single-blind randomized controlled clinical trial. Heliyon. 2023;9(5):e15865.

Abbas RL, Saab IM, Al-Sharif HK, Naja N, El-Khatib A. Effect of Adding Motorized Cycle Ergometer Over Exercise Training on Balance in Older Adults with Dementia: A Randomized Controlled Trial. Exp Aging Res. 2023;49(2):100–11.

Jetté M, Sidney K, Blümchen G. Metabolic equivalents (METS) in exercise testing, exercise prescription, and evaluation of functional capacity. Clin Cardiol. 1990;13(8):555–65.

Hills AP, Mokhtar N, Byrne NM. Assessment of physical activity and energy expenditure: an overview of objective measures. Front Nutr. 2014;1:5.

Eijsvogels TM, Thompson PD. Exercise is medicine: at any dose? JAMA. 2015;314(18):1915–6.

Lee I-M. Dose-response relation between physical activity and fitness: even a little is good; more is better. JAMA. 2007;297(19):2137–9.

Article   CAS   PubMed   Google Scholar  

White IR. Network meta-analysis. Stand Genomic Sci. 2015;15(4):951–85.

Cipriani A, Higgins JP, Geddes JR, Salanti G. Conceptual and technical challenges in network meta-analysis. Ann Intern Med. 2013;159(2):130–7.

RDC Team. R: A language and environment for statistical computing. 2010.

Pedder H. MBNMAdose: An R package for dose-response Model-Based Network Meta-Analysis models. 2020.

Wheeler DC, Hickson DA, Waller LA. Assessing local model adequacy in Bayesian hierarchical models using the partitioned deviance information criterion. Comput Stat Data Anal. 2010;54(6):1657–71.

Pedder H, Dias S, Bennetts M, Boucher M, Welton NJ. Modelling time-course relationships with multiple treatments: Model-based network meta-analysis for continuous summary outcomes. Research synthesis methods. 2019;10(2):267–86.

DerSimonian R, Kacker R. Random-effects model for meta-analysis of clinical trials: an update. Contemp Clin Trials. 2007;28(2):105–14.

Higgins JPT, Jackson D, Barrett J, Lu G, Ades A, White I. Consistency and inconsistency in network meta-analysis: concepts and models for multi-arm studies. Research synthesis methods. 2012;3(2):98–110.

Hu D, O’Connor AM, Wang C, Sargeant JM, Winder CB. How to conduct a Bayesian network meta-analysis. Frontiers in veterinary science. 2020;7:271.

Takeshima N, Sozu T, Tajika A, Ogawa Y, Hayasaka Y, Furukawa TA. Which is more generalizable, powerful and interpretable in meta-analyses, mean difference or standardized mean difference? BMC Med Res Methodol. 2014;14(1):1–7.

Hespanhol L, Vallio CS, Costa LM, Saragiotto BT. Understanding and interpreting confidence and credible intervals around effect estimates. Braz J Phys Ther. 2019;23(4):290–301.

Desquilbet L, Mariotti F. Dose-response analyses using restricted cubic spline functions in public health research. Stat Med. 2010;29(9):1037–57.

Higgins JP, Altman DG, Gøtzsche PC, Jüni P, Moher D, Oxman AD, Savović J, Schulz KF, Weeks L, Sterne JA. The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials. Bmj. 2011;343:d59282.

Minozzi S, Cinquini M, Gianola S, Gonzalez-Lorenzo M, Banzi R. The revised Cochrane risk of bias tool for randomized trials (RoB 2) showed low interrater reliability and challenges in its application. J Clin Epidemiol. 2020;126:37–44.

Minozzi S, Dwan K, Borrelli F, Filippini G. Reliability of the revised Cochrane risk-of-bias tool for randomised trials (RoB2) improved with the use of implementation instruction. J Clin Epidemiol. 2022;141:99–105.

Iyengar S, Greenhouse J. Sensitivity analysis and diagnostics. Handbook of research synthesis and meta-analysis. 2009:417–33.

Lautenschlager NT, Cox KL, Flicker L, Foster JK, Van Bockxmeer FM, Xiao J, Greenop KR, Almeida OP. Effect of physical activity on cognitive function in older adults at risk for Alzheimer disease: a randomized trial. JAMA. 2008;300(9):1027–37.

Kwak Y-S, Um S-Y, Son T-G, Kim D-J. Effect of regular exercise on senile dementia patients. Int J Sports Med. 2007;29:471–4.

Kemoun G, Thibaud M, Roumagne N, Carette P, Albinet C, Toussaint L, Paccalin M, Dugué B. Effects of a physical training programme on cognitive function and walking efficiency in elderly persons with dementia. Dement Geriatr Cogn Disord. 2010;29(2):109–14.

Tai S-Y, Hsu C-L, Huang S-W, Ma T-C, Hsieh W-C, Yang Y-H. Effects of multiple training modalities in patients with Alzheimer’s disease: a pilot study. Neuropsychiatr Dis Treat. 2016;12:2843–9.

Holthoff VA, Marschner K, Scharf M, Steding J, Meyer S, Koch R, Donix M. Effects of physical activity training in patients with Alzheimer’s dementia: results of a pilot RCT study. PLoS ONE. 2015;10(4):e0121478.

Bossers WJ, van der Woude LH, Boersma F, Hortobágyi T, Scherder EJ, van Heuvelen MJ. A 9-week aerobic and strength training program improves cognitive and motor function in patients with dementia: a randomized, controlled trial. Am J Geriatr Psychiatry. 2015;23(11):1106–16.

Telenius EW, Engedal K, Bergland A. Effect of a high-intensity exercise program on physical function and mental health in nursing home residents with dementia: an assessor blinded randomized controlled trial. PLoS ONE. 2015;10(5):e0126102.

Yang S-Y, Shan C-L, Qing H, Wang W, Zhu Y, Yin M-M, Machado S, Yuan T-F, Wu T. The effects of aerobic exercise on cognitive function of Alzheimer’s disease patients. CNS Neurol Disord Drug Targets. 2015;14(10):1292–7.

Cancela JM, Ayán C, Varela S, Seijo M. Effects of a long-term aerobic exercise intervention on institutionalized patients with dementia. J Sci Med Sport. 2016;19(4):293–8.

Hoffmann K, Sobol NA, Frederiksen KS, Beyer N, Vogel A, Vestergaard K, Brændgaard H, Gottrup H, Lolk A, Wermuth L. Moderate-to-high intensity physical exercise in patients with Alzheimer’s disease: a randomized controlled trial. J Alzheimers Dis. 2016;50(2):443–53.

Toots A, Littbrand H, Boström G, Hörnsten C, Holmberg H, Lundin-Olsson L, Lindelöf N, Nordström P, Gustafson Y, Rosendahl E. Effects of exercise on cognitive function in older people with dementia: a randomized controlled trial. J Alzheimers Dis. 2017;60(1):323–32.

Lamb SE, Sheehan B, Atherton N, Nichols V, Collins H, Mistry D, Dosanjh S, Slowther AM, Khan I, Petrou S. Dementia And Physical Activity (DAPA) trial of moderate to high intensity exercise training for people with dementia: randomised controlled trial. bmj. 2018;361:k1675.

Venturelli M, Scarsini R, Schena F. Six-month walking program changes cognitive and ADL performance in patients with Alzheimer. Am J Alzheimer’s Dis Other Dem. 2011;26(5):381–8.

Arcoverde C, Deslandes A, Moraes H, Almeida C. Araujo NBd, Vasques PE, Silveira H, Laks J: Treadmill training as an augmentation treatment for Alzheimer’s disease: a pilot randomized controlled study. Arq Neuropsiquiatr. 2014;72:190–6.

Gaitán JM, Boots EA, Dougherty RJ, Oh JM, Ma Y, Edwards DF, Christian BT, Cook DB, Okonkwo OC. Brain glucose metabolism, cognition, and cardiorespiratory fitness following exercise training in adults at risk for Alzheimer’s disease. Brain Plasticity. 2019;5(1):83–95.

Huang N, Li W, Rong X, Champ M, Wei L, Li M, Mu H, Hu Y, Ma Z, Lyu J. Effects of a modified Tai Chi program on older people with mild dementia: a randomized controlled trial. J Alzheimers Dis. 2019;72(3):947–56.

Nyman SR, Ingram W, Sanders J, Thomas PW, Thomas S, Vassallo M, Raftery J, Bibi I, Barrado-Martín Y. Randomised controlled trial of the effect of Tai Chi on postural balance of people with dementia. Clin Interv Aging. 2019;14:2017–29.

Sampaio A, Marques EA, Mota J, Carvalho J. Effects of a multicomponent exercise program in institutionalized elders with Alzheimer’s disease. Dementia. 2019;18(2):417–31.

Liu I-T, Lee W-J, Lin S-Y, Chang S-T, Kao C-L, Cheng Y-Y. Therapeutic effects of exercise training on elderly patients with dementia: a randomized controlled trial. Arch Phys Med Rehabil. 2020;101(5):762–9.

van Santen J, Dröes RM, Twisk JW, Henkemans OAB, van Straten A, Meiland FJ. Effects of exergaming on cognitive and social functioning of people with dementia: a randomized controlled trial. Journal of the American Medical Directors Association. 2020;21(12):1958-1967.e1955.

Liao Y-Y, Chen I-H, Hsu W-C, Tseng H-Y, Wang R-Y. Effect of exergaming versus combined exercise on cognitive function and brain activation in frail older adults: A randomised controlled trial. Ann Phys Rehabil Med. 2021;64(5):101492.

Yu F, Salisbury D, Mathiason MA. Inter-individual differences in the responses to aerobic exercise in Alzheimer’s disease: Findings from the FIT-AD trial. J Sport Health Sci. 2021;10(1):65–72.

Yu F, Vock DM, Zhang L, Salisbury D, Nelson NW, Chow LS, Smith G, Barclay TR, Dysken M, Wyman JF. Cognitive effects of aerobic exercise in Alzheimer’s disease: a pilot randomized controlled trial. J Alzheimers Dis. 2021;80(1):233–44.

Borges-Machado F, Teixeira L, Carvalho J, Ribeiro O. Does Multicomponent Physical Exercise Training Work for Dementia? Exploring the Effects on Cognition, Neuropsychiatric Symptoms, and Quality of Life. J Geriatr Psychiatry Neurol. 2023;36(5):376–85.

Vreugdenhil A, Cannell J, Davies A, Razay G. A community-based exercise programme to improve functional ability in people with Alzheimer’s disease: A randomized controlled trial. Scand J Caring Sci. 2012;26(1):12–9.

Rouse B, Chaimani A, Li T. Network meta-analysis: an introduction for clinicians. Intern Emerg Med. 2017;12:103–11.

Bull FC, Al-Ansari SS, Biddle S, Borodulin K, Buman MP, Cardon G, Carty C, Chaput J-P, Chastin S, Chou R. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. Br J Sports Med. 2020;54(24):1451–62.

Larson EB, Wang L, Bowen JD, McCormick WC, Teri L, Crane P, Kukull W. Exercise is associated with reduced risk for incident dementia among persons 65 years of age and older. Ann Intern Med. 2006;144(2):73–81.

Huang X, Zhao X, Li B, Cai Y, Zhang S, Wan Q, Yu F. Comparative efficacy of various exercise interventions on cognitive function in patients with mild cognitive impairment or dementia: a systematic review and network meta-analysis. J Sport Health Sci. 2022;11(2):212–23.

Franklin BA, Brinks J, Berra K, Lavie CJ, Gordon NF, Sperling LS. Using metabolic equivalents in clinical practice. Am J Cardiol. 2018;121(3):382–7.

Bynum JP. The long reach of Alzheimer’s disease: patients, practice, and policy. Health Aff. 2014;33(4):534–40.

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Additional file 1: Appendix 1. Search Strategy. Appendix 2. Transformation formulas for estimating the mean and standard deviation. Appendix 3. Characteristics of the dataset and included studies. Appendix 4. Key Assumptions of Network Meta-Analysis. Appendix 5. Nonlinear function and model fit comparison. Appendix 6. Ranking of the effectiveness of interventions. Appendix 7. Study level Risk of Bias analysis. Appendix 8. Sensitivity analysis including only studies with low risk of bias. Appendix 9. The list of included studies.

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Yuan, Y., Yang, Y., Hu, X. et al. Effective dosage and mode of exercise for enhancing cognitive function in Alzheimer's disease and dementia: a systematic review and Bayesian Model-Based Network Meta-analysis of RCTs. BMC Geriatr 24 , 480 (2024). https://doi.org/10.1186/s12877-024-05060-8

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Differential attainment in assessment of postgraduate surgical trainees: a scoping review

  • Rebecca L. Jones 1 , 2 ,
  • Suwimol Prusmetikul 1 , 3 &
  • Sarah Whitehorn 1  

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Solving disparities in assessments is crucial to a successful surgical training programme. The first step in levelling these inequalities is recognising in what contexts they occur, and what protected characteristics are potentially implicated.

This scoping review was based on Arksey & O’Malley’s guiding principles. OVID and Embase were used to identify articles, which were then screened by three reviewers.

From an initial 358 articles, 53 reported on the presence of differential attainment in postgraduate surgical assessments. The majority were quantitative studies (77.4%), using retrospective designs. 11.3% were qualitative. Differential attainment affects a varied range of protected characteristics. The characteristics most likely to be investigated were gender (85%), ethnicity (37%) and socioeconomic background (7.5%). Evidence of inequalities are present in many types of assessment, including: academic achievements, assessments of progression in training, workplace-based assessments, logs of surgical experience and tests of technical skills.

Attainment gaps have been demonstrated in many types of assessment, including supposedly “objective” written assessments and at revalidation. Further research is necessary to delineate the most effective methods to eliminate bias in higher surgical training. Surgical curriculum providers should be informed by the available literature on inequalities in surgical training, as well as other neighbouring specialties such as medicine or general practice, when designing assessments and considering how to mitigate for potential causes of differential attainment.

Peer Review reports

Diversity in the surgical workforce has been a hot topic for the last 10 years, increasing in traction following the BlackLivesMatter movement in 2016 [ 1 ]. In the UK this culminated in publication of the Kennedy report in 2021 [ 2 ]. Before this the focus was principally on gender imbalance in surgery, with the 2010 Surgical Workforce report only reporting gender percentages by speciality, with no comment on racial profile, sexuality distribution, disability occurrence, or socioeconomic background [ 3 ].

Gender is not the only protected characteristic deserving of equity in surgery; many groups find themselves at a disadvantage during postgraduate surgical examinations [ 4 ] and at revalidation [ 5 ]. This phenomenon is termed ‘differential attainment’ (DA), in which disparities in educational outcomes, progression rates, or achievements between groups with protected characteristics occur [ 4 ]. This may be due to the assessors’ subconscious bias, or a deficit in training and education before assessment.

One of the four pillars of medical ethics is “justice”, emphasising that healthcare should be provided in a fair, equitable, and ethical manner, benefiting all individuals and promoting the well-being of society as a whole. This applies not only to our patients but also to our colleagues; training should be provided in a fair, equitable, and ethical manner, benefiting all. By applying the principle of justice to surgical trainees, we can create an environment that is supportive, inclusive, and conducive to professional growth and well-being.

A diverse consultant body is crucial for providing high-quality healthcare to a diverse patient population. It has been shown that patients are happier when cared for by a doctor with the same ethnic background [ 6 ]. Takeshita et al. [ 6 ] proposed this is due to a greater likelihood of mutual understanding of cultural values, beliefs, and preferences and is therefore more likely to cultivate a trusting relationship, leading to accurate diagnosis, treatment adherence and improved patient understanding. As such, ensuring that all trainees are justly educated and assessed throughout their training may contribute to improving patient care by diversifying the consultant body.

Surgery is well known to have its own specific culture, language, and social rules which are unique even within the world of medicine [ 7 , 8 ]. Through training, graduates develop into surgeons, distinct from other physicians and practitioners [ 9 ]. As such, research conducted in other medical domains is not automatically applicable to surgery, and behavioural interventions focused on reducing or eliminating bias in training need to be tailored specifically to surgical settings.

Consequently, it’s important that the surgical community asks the questions:

Does DA exist in postgraduate surgical training, and to what extent?

Why does DA occur?

What groups or assessments are under-researched?

How can we apply this knowledge, or acquire new knowledge, to provide equity for trainees?

The following scoping review hopes to provide the surgical community with robust answers for future of surgical training.

Aims and research question

The aim of this scoping review is to understand the breadth of research about the presence of DA in postgraduate surgical education and to determine themes pertaining to causes of inequalities. A scoping review was chosen to provide a means to map the available literature, including published peer-reviewed primary research and grey literature.

Following the methodological framework set out by Arksey and O’Malley [ 10 ], our research was intended to characterise the literature addressing DA in HST, including Ophthalmology, Obstetrics & Gynaecology (O&G). We included literature from English-language speaking countries, including the UK and USA.

Search strategy

We used search terms tailored to our target population characteristics (e.g., gender, ethnicity), concept (i.e., DA) and context (i.e., assessment in postgraduate surgical education). Medline and Embase were searched with the assistance of a research librarian, with addition of synonyms. This was conducted in May 2023, and was exported to Microsoft Excel for further review. The reference lists of included articles were also searched to find any relevant data sources that had yet to be considered. In addition, to identify grey literature, a search was performed for the term “differential attainment” and “disparity” on the relevant stakeholders’ websites (See supplemental Table 1 for full listing). Stakeholders were included on the basis of their involvement in governance or training of surgical trainees.

Study selection

To start we excluded conference abstracts that were subsequently published as full papers to avoid duplications ( n  = 337). After an initial screen by title to exclude obviously irrelevant articles, articles were filtered to meet our inclusion and exclusion criteria (Table  1 ). The remaining articles ( n  = 47) were then reviewed in their entirety, with the addition of five reports found in grey literature. Following the screening process, 45 studies were recruited for scoping review (Fig.  1 ).

Charting the data

The extracted data included literature title, authors, year of publication, country of study, study design, population characteristic, case number, context, type of assessment, research question and main findings (Appendix 1). Extraction was performed initially by a single author and then subsequently by a second author to ensure thorough review. Group discussion was conducted in case of any disagreements. As charting occurred, papers were discovered within reference lists of included studies which were eligible for inclusion; these were assimilated into the data charting table and included in the data extraction ( n  = 8).

Collating, summarizing and reporting the results

The included studies were not formally assessed in their quality or risk of bias, consistent with a scoping review approach [ 10 ]. However, group discussion was conducted during charting to aid argumentation and identify themes and trends.

We conducted a descriptive numerical summary to describe the characteristics of included studies. Then thematic analysis was implemented to examine key details and organise the attainment quality and population characteristics based on their description. The coding of themes was an iterative process and involved discussion between authors, to identify and refine codes to group into themes.

We categorised the main themes as gender, ethnicity, country of graduation, individual and family background in education, socioeconomic background, age, and disability. The number of articles in each theme is demonstrated in Table  2 . Data was reviewed and organised into subtopics based on assessment types included: academic achievement (e.g., MRCS, FRCS), assessments for progression (e.g., ARCP), workplace-based assessment (e.g., EPA, feedback), surgical experience (e.g., case volume), and technical skills (e.g., visuo-spatial tasks).

figure 1

PRISMA flow diagram

44 articles defined the number of included participants (89,399 participants in total; range of participants across individual studies 16–34,755). Two articles reported the number of included studies for their meta-analysis (18 and 63 included articles respectively). Two reports from grey literature did not define the number of participants they included in their analysis. The characteristics of the included articles are displayed in Table  2 .

figure 2

Growth in published literature on differential attainment over the past 40 years

Academic achievement

In the American Board of Surgery Certifying Exam (ABSCE), Maker [ 11 ] found there to be no significant differences in terms of gender when comparing those who passed on their first attempt and those who did not in general surgery training, a finding supported by Ong et al. [ 12 ]. Pico et al. [ 13 ] reported that in Orthopaedic training, Orthopaedic In-Training Examination (OITE) and American Board of Orthopaedic Surgery (ABOS) Part 1 scores were similar between genders, but that female trainees took more attempts in order to pass. In the UK, two studies reported significantly lower Membership of the Royal College of Surgeons (MRCS) pass rates for female trainees compared to males [ 4 , 14 ]. However, Robinson et al. [ 15 ] presented no significant gender differences in MRCS success rates. A study assessing Fellowship of the Royal College of Surgeons (FRCS) examination results found no significant gender disparities in pass rates [ 16 ]. In MRCOG examination, no significant gender differences were found in Part 1 scores, but women had higher pass rates and scores in Part 2 [ 17 ].

Assessment for Progression

ARCP is the annual process of revalidation that UK doctors must perform to progress through training. A satisfactory progress outcome (“outcome 1”) allows trainees to advance through to the next training year, whereas non-satisfactory outcomes (“2–5”) suggest inadequate progress and recommends solutions, such as further time in training or being released from the training programme. Two studies reported that women received 60% more non-satisfactory outcomes than men [ 16 , 18 ]. In contrast, in O&G men had higher non-satisfactory ARCP outcomes without explicit reasons for this given [ 19 ].

Regarding Milestone evaluations based from the US Accreditation Council for Graduate Medical Education (ACGME), Anderson et al. [ 20 ] reported men had higher ratings of knowledge of diseases at postgraduate year 5 (PGY-5), while women had lower mean score achievements. This was similar to another study finding that men and women had similar competencies at PGY-1 to 3, and that it was only at PGY-5 that women were evaluated lower than men [ 21 ]. However, Kwasny et al. [ 22 ] found no difference in trainers’ ratings between genders, but women self-rated themselves lower. Salles et al. [ 23 ] demonstrated significant improvement in scoring in women following a value-affirmation intervention, while this intervention did not affect men.

Workplace-based Assessment

Galvin et al. [ 24 ] reported better evaluation scores from nurses for PGY-2 male trainees, while females received fewer positive and more negative comments. Gerull et al. [ 25 ] demonstrated men received compliments with superlatives or standout words, whereas women were more likely to receive compliments with mitigating phrases (e.g., excellent vs. quite competent).

Hayward et al. [ 26 ] investigated assessment of attributes of clinical performance (ethics, judgement, technical skills, knowledge and interpersonal skills) and found similar scoring between genders.

Several authors have studied autonomy given to trainees in theatre [ 27 , 28 , 29 , 30 , 31 ]. Two groups found no difference in level of granted autonomy between genders but that women rated lower perceived autonomy on self-evaluation [ 27 , 28 ]. Other studies found that assessors consistently gave female trainees lower autonomy ratings, but only in one paper was this replicated in lower performance scores [ 29 , 30 , 31 ].

Padilla et al. [ 32 ] reported no difference in entrustable professional activity assessment (EPA) levels between genders, yet women rated themselves much lower, which they regarded as evidence of imposter syndrome amongst female trainees. Cooney et al. [ 33 ] found that male trainers scored EPAs for women significantly lower than men, while female trainers rated both genders similarly. Conversely, Roshan et al. [ 34 ] found that male assessors were more positive in feedback comments to female trainees than male trainees, whereas they also found that comments from female assessors were comparable for each gender.

Surgical Experience

Gong et al. [ 35 ] found significantly fewer cataract operations were performed by women in ophthalmology residency programmes, which they suggested could be due to trainers being more likely to give cases to male trainees. Female trainees also participated in fewer robotic colorectal procedures, with less operative time on the robotic console afforded [ 36 ]. Similarly, a systematic review highlighted female trainees in various specialties performed fewer cases per week and potentially had limited access to training facilities [ 37 ]. Eruchalu et al. [ 38 ] found that female trainees performed fewer cases, that is, until gender parity was reached, after which case logs were equivalent.

Technical skills

Antonoff et al. [ 39 ] found higher scores for men in coronary anastomosis skills, with women receiving more “fail” assessments. Dill-Macky et al. [ 40 ] analysed laparoscopic skill assessment using blinded videos of trainees and unblinded assessments. While there was no difference in blinded scores between genders, when comparing blinded and unblinded scores individually, assessors were less likely to agree on the scores of women compared to men. However, another study about laparoscopic skills by Skjold-Ødegaard et al. [ 41 ] reported higher performance scores in female residents, particularly when rated by women. The lowest score was shown in male trainees rated by men. While some studies showed disparities in assessment, several studies reported no difference in technical skill assessments (arthroscopic, knot tying, and suturing skills) between genders [ 42 , 43 , 44 , 45 , 46 ].

Several studies investigated trainees’ abilities to complete isolated tasks associated with surgical skills. In laparoscopic tasks, men were initially more skilful in peg transfer and intracorporeal knot tying than women. Following training, the performance was not different between genders [ 47 ]. A study on microsurgical skills reported better initial visual-spatial and perceptual ability in men, while women had better fine motor psychomotor ability. However, these differences were not significant, and all trainees improved significantly after training [ 48 ]. A study by Milam et al. [ 49 ] revealed men performed better in mental rotation tasks and women outperformed in working memory. They hypothesised that female trainees would experience stereotype threat, fear of being reduced to a stereotype, which would impair their performance. They found no evidence of stereotype threat influencing female performance, disproving their hypothesis, a finding supported by Myers et al. [ 50 ].

Ethnicity and country of graduation

Most papers reported ethnicity and country of graduation concurrently, for example grouping trainees as White UK graduates (WUKG), Black and minority ethnicity UK graduates (BME UKG), and international medical graduates (IMG). Therefore, these areas will be addressed together in the following section.

When assessing the likelihood of passing American Board of Surgery (ABS) examinations on first attempt, Yeo et al. [ 51 ] found that White trainees were more likely than non-White. They found that the influence of ethnicity was more significant in the end-of-training certifying exam than in the start-of-training qualifying exam. This finding was corroborated in a study of both the OITE and ABOS certifying exam, suggesting widening inequalities during training [ 52 ].

Two UK-based studies reported significantly higher MRCS pass rates in White trainees compared to BMEs [ 4 , 14 ]. BMEs were less likely to pass MRCS Part A and B, though this was not true for Part A when variations in socioeconomic background were corrected for [ 14 ]. However, Robinson et al. [ 53 ] found no difference in MRCS pass rates based on ethnicity. Another study by Robinson et al. [ 15 ] demonstrated similar pass rates between WUKGs and BME UKGs, but IMGs had significantly lower pass rates than all UKGs. The FRCS pass rates of WUKGs, BME UKGs and IMGs were 76.9%, 52.9%, and 53.9%, respectively, though these percentages were not statistically significantly different [ 16 ].

There was no difference in MRCOG results based on ethnicity, but higher success rates were found in UKGs [ 19 ]. In FRCOphth, WUKGs had a pass rate of 70%, higher than other groups of trainees, with a pass rate of only 45% for White IMGs [ 52 ].

By gathering data from training programmes reporting little to no DA due to ethnicity, Roe et al. [ 54 ] were able to provide a list of factors they felt were protective against DA, such as having supportive supervisors and developing peer networks.

Assessment for progression

RCOphth [ 55 ] found higher rates of satisfactory ARCP outcomes for WUKGs compared to BME UKGs, followed by IMGs. RCOG [ 19 ] discovered higher rates of non-satisfactory ARCP outcomes from non-UK graduates, particularly amongst BMEs and those from the European Economic Area (EEA). Tiffin et al. [ 56 ] considered the difference in experience between UK graduates and UK nationals whose primary medical qualification was gained outside of the UK, and found that the latter were more likely to receive a non-satisfactory ARCP outcome, even when compared to non-UK nationals.

Woolf et al. [ 57 ] explored reasons behind DA by conducting interview studies with trainees. They investigated trainees’ perceptions of fairness in evaluation and found that trainees felt relationships developed with colleagues who gave feedback could affect ARCP results, and might be challenging for BME UKGs and IMGs who have less in common with their trainers.

Workplace-based assessment

Brooks et al. [ 58 ] surveyed the prevalence of microaggressions against Black orthopaedic surgeons during assessment and found 87% of participants experienced some level of racial discrimination during workplace-based performance feedback. Black women reported having more racially focused and devaluing statements from their seniors than men.

Surgical experience

Eruchalu et al. [ 38 ] found that white trainees performed more major surgical cases and more cases as a supervisor than did their BME counterparts.

Dill-Macky et al. [ 40 ] reported no significant difference in laparoscopic surgery assessments between ethnicities.

Individual and family background in education

Two studies [ 4 , 16 ] concentrated on educational background, considering factors such as parental occupation and attendance of a fee-paying school. MRCS part A pass rate was significantly higher for trainees for whom Medicine was their first Degree, those with university-educated parents, higher POLAR (Participation In Local Areas classification group) quintile, and those from fee-paying schools. Higher part B pass rate was associated with graduating from non-Graduate Entry Medicine programmes and parents with managerial or professional occupations [ 4 ]. Trainees with higher degrees were associated with an almost fivefold increase in FRCS success and seven times more scientific publications than their counterparts [ 16 ].

Socioeconomic background

Two studies used Index of Multiple Deprivation quintile, the official measure of relative deprivation in England based on geographical areas for grading socioeconomic level. The area was defined at the time of medical school application. Deprivation quintiles (DQ) were calculated, ranging from DQ1 (most deprived) to DQ5 (least deprived) [ 4 , 14 ].

Trainees with history of less deprivation were associated with higher MRCS part A pass rate. More success in part B was associated with history of no requirement for income support and less deprived areas [ 4 ]. Trainees from DQ1 and DQ2 had lower pass rates and higher number of attempts to pass [ 14 ]. A general trend of better outcomes in examination was found from O&G trainees in less deprived quintiles [ 19 ].

Trainees from DQ1 and DQ2 received significantly more non-satisfactory ARCP outcomes (24.4%) than DQ4 and DQ5 (14.2%) [ 14 ].

Trainees who graduated at age less than 29 years old were more likely to pass MRCS than their counterparts [ 4 ].

Authors [ 18 , 56 ] found that older trainees received more non-satisfactory ARCP outcomes. Likewise, there was higher percentage of non-satisfactory ARCP outcomes in O&G trainees aged over 45 compared with those aged 25–29 regardless of gender [ 19 ].

Trainees with disability had significantly lower pass rates in MRCS part A compared to candidates without disability. However, the difference was not significant for part B [ 59 ].

What have we learnt from the literature?

It is heartening to note the recent increase in interest in DA (27 studies in the last 4 years, compared to 26 in the preceding 40) (Fig.  2 ). The vast majority (77%) of studies are quantitative, based in the US or UK (89%), focus on gender (85%) and relate to clinical assessments (51%) rather than examination results. Therefore, the surgical community has invested primarily in researching the experience of women in the USA and UK.

Interestingly, a report by RCOG [ 19 ] showed that men were more likely to receive non-satisfactory ARCP outcomes than women, and a study by Rushd et al. [ 17 ] found that women were more likely to pass part 2 of MRCOG than men. This may be because within O&G men are the “out-group” (a social group or category characterised by marginalisation or exclusion by the dominant cultural group) as 75% of O&G trainees are female [ 60 ].

This contrasts with other specialities in which men are the in-group and women are seen to underperform. Outside of O&G, in comparison to men, women are less likely to pass MRCS [ 4 , 14 ], receive satisfactory ARCP outcome [ 16 , 18 ], or receive positive feedback [ 24 ], whilst not performing the same number of procedures as men [ 34 , 35 ]. This often leads to poor self-confidence in women [ 32 ], which can then worsen performance [ 21 ].

It proves difficult to comment on DA for many groups due to a lack of evidence. The current research suggests that being older, having a disability, graduate entry to medicine, low parental education, and living in a lower socioeconomic area at the time of entering medical school are all associated with lower MRCS pass rates. Being older and having a lower socioeconomic background are also associated with non-satisfactory ARCP outcomes, slowing progression through training.

These characteristics may provide a compounding negative effect – for example having a previous degree will automatically make a trainee older, and living in a lower socioeconomic area makes it more likely their parents will have a non-professional job and not hold a higher degree. When multiple protected characteristics interact to produce a compounded negative effect for a person, it is often referred to as “intersectional discrimination” or “intersectionality” [ 61 ]. This is a concept which remains underrepresented in the current literature.

The literature is not yet in agreement over the presence of DA due to ethnicity. There are many studies that report perceived discrimination, however the data for exam and clinical assessment outcomes is equivocal. This may be due to the fluctuating nature of in-groups and out-groups, and multiple intersecting characteristics. Despite this, the lived experience of BME surgeons should not be ignored and requires further investigation.

What are the gaps in the literature?

The overwhelming majority of literature exploring DA addresses issues of gender, ethnicity or country of medical qualification. Whilst bias related to these characteristics is crucial to recognise, studies into other protected characteristics are few and far between. The only paper on disability reported striking differences in attainment between disabled and non-disabled registrars [ 59 ]. There has also been increased awareness about neurodiversity amongst doctors and yet an exploration into the experience of neurodiverse surgeons and their progress through training has yet to be published [ 62 ].

The implications of being LGBTQ + in surgical training have not been recognised nor formally addressed in the literature. Promisingly, the experiences of LGBTQ + medical students have been recognised at an undergraduate level, so one can hope that this will be translated into postgraduate education [ 63 , 64 ]. While this is deeply entwined with experiences of gender discrimination, it is an important characteristic that the surgical community would benefit from addressing, along with disability. To a lesser extent, the effect of socioeconomic background and age have also been overlooked.

Characterising trainees for the purpose of research

Ethnicity is deeply personal, self-defined, and may change over time as personal identity evolves, and therefore arbitrarily grouping diverse ethnic backgrounds is unlikely to capture an accurate representation of experiences. There are levels of discrimination even within minority groups; colourism in India means dark-skinned Indians will experience more discrimination than light-skinned Indians, even from those within in their own ethnic group [ 65 ]. Therefore, although the studies included in the scoping review accepted self-definitions of ethnicity, this is likely not enough to fully capture the nuances of bias and discrimination present in society. For example, Ellis et al. [ 4 ] grouped participants as “White”, “Mixed”, “Asian”, “Black” and “Other”, however they could have also assigned a skin tone value such as the NIS Skin Colour Scale [ 66 ], thus providing more detail.

Ethnicity is more than genetic heritage; it is also cultural expression. The experience of an IMG in UK postgraduate training will differ from that of a UKG, an Indian UKG who grew up in India, and an Indian UKG who grew up in the UK. These are important distinctions which are noted in the literature (e.g. by Woolf et al., 2016 [ 57 ]) however some do not distinguish between ethnicity and graduate status [ 15 ] and none delve into an individual’s cultural expression (e.g., clothing choice) and how this affects the perception of their assessors.

Reasons for DA

Despite the recognition of inequalities in all specialties of surgery, there is a paucity of data explicitly addressing why DA occurs. Reasons behind the phenomenon must be explored to enable change and eliminate biases. Qualitative research is more attuned to capturing the complexities of DA through observation or interview-based studies. Currently most published data is quantitative, and relies on performance metrics to demonstrate the presence of DA while ignoring the causes. Promisingly, there are a gradually increasing number of qualitative, predominantly interview-based, studies (Fig.  2 ).

To create a map of DA in all its guises, an analysis of the themes reported to be contributory to its development is helpful. In our review of the literature, four themes have been identified:

Training culture

In higher surgical training, for there to be equality in outcomes, there needs to be equity in opportunities. Ellis et al. [ 4 ] recognised that variation in training experiences, such as accessibility of supportive peers and senior role models, can have implications on attainment. Trainees would benefit from targeted support at times of transition, such as induction or at examinations, and it may be that currently the needs of certain groups are being met before others, reinforcing differential attainment [ 4 ].

Experience of assessment

Most literature in DA relates to the presence (or lack of) an attainment gap in assessments, such as ARCP or MRCS. It is assumed that these assessments of trainee development are objective and free of bias, and indeed several authors have described a lack of bias in these high-stakes examinations (e.g., Ong et al., 2019 [ 12 ]; Robinson et al., 2019 [ 53 ]). However, in some populations, such as disabled trainees, there are differences in attainment [ 59 ]. This is demonstrated despite legislation requiring professional bodies to make reasonable adjustments to examinations for disabled candidates, such as additional time, text formatting amendments, or wheelchair-accessible venues [ 67 ]. Therefore it would be beneficial to investigate the implementation of these adjustments across higher surgical examinations and identify any deficits.

Social networks

Relationships between colleagues may influence DA in multiple ways. Several studies identified that a lack of a relatable and inspiring mentor may explain why female or BME doctors fail to excel in surgery [ 4 , 55 ]. Certain groups may receive preferential treatment due to their perceived familiarity to seniors [ 35 ]. Robinson et al. [ 15 ] recognised that peer-to-peer relationships were also implicated in professional development, and the lack thereof could lead to poor learning outcomes. Therefore, a non-discriminatory culture and inclusion of trainees within the social network of training is posited as beneficial.

Personal characteristics

Finally, personal factors directly related to protected characteristics have been suggested as a cause of DA. For example, IMGs may perform worse in examinations due to language barriers, and those from disadvantaged backgrounds may have less opportunity to attend expensive courses [ 14 , 16 ]. Although it is impossible to exclude these innate deficits from training, we may mitigate their influence by recognising their presence and providing solutions.

The causes of DA may also be grouped into three levels, as described by Regan de Bere et al. [ 68 ]: macro (the implications of high-level policy), meso (focusing on institutional or working environments) and micro (the influence of individual factors). This can intersect with the four themes identified above, as training culture can be enshrined at both an institutional and individual level, influencing decisions that relate to opportunities for trainees, or at a macro level, such as in the decisions made on nationwide recruitment processes. These three levels can be used to more deeply explore each of the four themes to enrich the discovery of causes of DA.

Discussions outside of surgery

Authors in General Practice (e.g., Unwin et al., 2019 [ 69 ]; Pattinson et al., 2019 [ 70 ]), postgraduate medical training (e.g., Andrews, Chartash, and Hay, 2021 [ 71 ]), and undergraduate medical education (e.g., Yeates et al., 2017 [ 72 ]; Woolf et al., 2013 [ 73 ]) have published more extensively in the aetiology of DA. A study by Hope et al. [ 74 ] evaluating the bias present in MRCP exams used differential item functioning to identify individual questions which demonstrated an attainment gap between male and female and Caucasian and non-Caucasian medical trainees. Conclusions drawn about MRCP Part 1 examinations may be generalisable to MRCS Part A or FRCOphth Part 1: they are all multiple-choice examinations testing applied basic science and usually taken within the first few years of postgraduate training. Therefore it is advisable that differential item functioning should also be applied to these examinations. However, it is possible that findings in some subspecialities may not be generalisable to others, as training environments can vary profoundly. The RCOphth [ 55 ] reported that in 2021, 53% of ophthalmic trainees identified as male, whereas in Orthopaedics 85% identified as male, suggesting different training environments [ 5 ]. It is useful to identify commonalities of DA between surgical specialties and in the wider scope of medical training.

Limitations of our paper

Firstly, whilst aiming to provide a review focussed on the experience of surgical trainees, four papers contained data about either non-surgical trainees or medical students. It is difficult to draw out the surgeons from this data and therefore it is possible that there are issues with generalisability. Furthermore, we did not consider the background of each paper’s authors, as their own lived experience of attainment gap could form the lens through which they commented on surgical education, colouring their interpretation. Despite intending to include as many protected characteristics as possible, inevitably there will be lived experiences missed. Lastly, the experience of surgical trainees outside of the English-speaking world were omitted. No studies were found that originated outside of Europe or North America and therefore the presence or characteristics of DA outside of this area cannot be assumed.

Experiences of inequality in surgical assessment are prevalent in all surgical subspecialities. In order to further investigate DA, researchers should ensure all protected characteristics are considered - and how these interact - to gain insight into intersectionality. Given the paucity of current evidence, particular focus should be given to the implications of disability, and specifically neurodiversity, in progress through training as they are yet to be explored in depth. In defining protected characteristics, future authors should be explicit and should avoid generalisation of cultural backgrounds to allow authentic appreciation of attainment gap. Few authors have considered the driving forces between bias in assessment and DA, and therefore qualitative studies should be prioritised to uncover causes for and protective factors against DA. Once these influences have been identified, educational designers can develop new assessment methods that ensure equity across surgical trainees.

Data availability

All data provided during this study are included in the supplementary information files.


Accreditation Council for Graduate Medical Education

American Board of Orthopaedic Surgery

American Board of Surgery

American Board of Surgery Certifying Exam

Annual Review of Competence Progression

Black, Asian, and Minority Ethnicity

Council on Resident Education in Obstetrics and Gynecology

Differential Attainment

Deprivation Quintile

European Economic Area

Entrustable Professional Activities

Fellowship of The Royal College of Ophthalmologists

Fellow of the Royal College of Surgeons

General Medical Council

Higher Surgical Training

International Medical Graduate

In-Training Evaluation Report

Member of the Royal College of Obstetricians and Gynaecologists

Member of the Royal College of Physicians

Member of the Royal College of Surgeons

Obstetrics and Gynaecology

Orthopaedic In-Training Examination

Participation In Local Areas

Postgraduate Year

The Royal College of Ophthalmologists

The Royal College of Obstetricians and Gynaecologists

The Royal College of Surgeons of England

United Kingdom Graduate

White United Kingdom Graduate

Joseph JP, Joseph AO, Jayanthi NVG, et al. BAME Underrepresentation in Surgery Leadership in the UK and Ireland in 2020: An Uncomfortable Truth. The Bulletin of the Royal College of Surgeons of England. 2020; 102 (6): 232–33.

Royal College of Surgeons of England. The Royal College – Our Professional Home. An independent review on diversity and inclusion for the Royal College of Surgeons of England. Review conducted by Baroness Helena Kennedy QC. RCS England. 2021.

Sarafidou K, Greatorex R. Surgical workforce: planning today for the workforce of the future. Bull Royal Coll Surg Engl. 2011;93(2):48–9. https://doi.org/10.1308/147363511X552575 .

Article   Google Scholar  

Ellis R, Brennan P, Lee AJ, et al. Differential attainment at MRCS according to gender, ethnicity, age and socioeconomic factors: a retrospective cohort study. J R Soc Med. 2022;115(7):257–72. https://doi.org/10.1177/01410768221079018 .

Hope C, Humes D, Griffiths G, et al. Personal Characteristics Associated with Progression in Trauma and Orthopaedic Specialty Training: A Longitudinal Cohort Study.Journal of Surgical Education 2022; 79 (1): 253–59. doi:10.1016/j.jsurg.2021.06.027.

Takeshita J, Wang S, Loren AW, et al. Association of Racial/Ethnic and Gender Concordance Between Patients and Physicians With Patient Experience Ratings. JAMA Network Open. 2022; 3(11). doi:10.1001/jamanetworkopen.2020.24583.

Katz, P. The Scalpel’s Edge: The Culture of Surgeons. Allyn and Bacon, 1999.

Tørring B, Gittell JH, Laursen M, et al. (2019) Communication and relationship dynamics in surgical teams in the operating room: an ethnographic study. BMC Health Services Research. 2019;19, 528. doi:10.1186/s12913-019-4362-0.

Veazey Brooks J & Bosk CL. (2012) Remaking surgical socialization: work hour restrictions, rites of passage, and occupational identity. Social Science & Medicine. 2012;75(9):1625-32. doi: 10.1016/j.socscimed.2012.07.007.

Arksey H & OʼMalley L. Scoping studies: Towards a methodological framework. International Journal of Social Research Methodology. 2005;8(1), 19–32.

Maker VK, Marco MZ, Dana V, et al. Can We Predict Which Residents Are Going to Pass/Fail the Oral Boards? Journal of Surgical Education. 2012;69 (6): 705–13.

Ong TQ, Kopp JP, Jones AT, et al. Is there gender Bias on the American Board of Surgery general surgery certifying examination? J Surg Res. 2019;237:131–5. https://doi.org/10.1016/j.jss.2018.06.014 .

Pico K, Gioe TJ, Vanheest A, et al. Do men outperform women during orthopaedic residency training? Clin Orthop Relat Res. 2010;468(7):1804–8. https://doi.org/10.1007/s11999-010-1318-4 .

Vinnicombe Z, Little M, Super J, et al. Differential attainment, socioeconomic factors and surgical training. Ann R Coll Surg Engl. 2022;104(8):577–82. https://doi.org/10.1308/rcsann.2021.0255 .

Robinson DBT, Hopkins L, James OP, et al. Egalitarianism in surgical training: let equity prevail. Postgraduate Medical Journal. 2020;96 (1141), 650–654. doi:10.1136/postgradmedj-2020-137563.

Luton OW, Mellor K, Robinson DBT, et al. Differential attainment in higher surgical training: scoping pan-specialty spectra. Postgraduate Medical Journal. 2022;99(1174),849–854. doi:10.1136/postgradmedj-2022-141638.

Rushd S, Landau AB, Khan JA, Allgar V & Lindow SW. An analysis of the performance of UK medical graduates in the MRCOG Part 1 and Part 2 written examinations. Postgraduate Medical Journal. 2012;88 (1039), 249–254. doi:10.1136/postgradmedj-2011-130479.

Hope C, Lund J, Griffiths G, et al. Differences in ARCP outcome by surgical specialty: a longitudinal cohort study. Br J Surg. 2021;108. https://doi.org/10.1093/bjs/znab282.051 .

Royal College of Obstetricians and Gynaecologists. Report Differential Attainment 2019. https://www.rcog.org.uk/media/jscgfgwr/differential-attainment-tef-report-2019.pdf [Last accessed 28/12/23].

Anderson JE, Zern NK, Calhoun KE, et al. Assessment of Potential Gender Bias in General Surgery Resident Milestone Evaluations. JAMA Surgery. 2022;157 (12), 1164–1166. doi:10.1001/jamasurg.2022.3929.

Landau SI, Syvyk S, Wirtalla C, et al. Trainee Sex and Accreditation Council for Graduate Medical Education Milestone Assessments during general surgery residency. JAMA Surg. 2021;156(10):925–31. https://doi.org/10.1001/jamasurg.2021.3005 .

Kwasny L, Shebrain S, Munene G, et al. Is there a gender bias in milestones evaluations in general surgery residency training? Am J Surg. 2021;221(3):505–8. https://doi.org/10.1016/j.amjsurg.2020.12.020 .

Salles A, Mueller CM & Cohen GL. A Values Affirmation Intervention to Improve Female Residents’ Surgical Performance. Journal of Graduate Medical Education. 2016;8 (3), 378–383. doi:10.4300/JGME-D-15-00214.1.

Galvin S, Parlier A, Martino E, et al. Gender Bias in nurse evaluations of residents in Obstetrics and Gynecology. Obstet Gynecol. 2015;126(7S–12S). https://doi.org/10.1097/AOG.0000000000001044 .

Gerull KM, Loe M, Seiler K, et al. Assessing gender bias in qualitative evaluations of surgical residents. Am J Surg. 2019;217(2):306–13. https://doi.org/10.1016/j.amjsurg.2018.09.029 .

Hayward CZ, Sachdeva A, Clarke JR. Is there gender bias in the evaluation of surgical residents? Surgery. 1987;102(2):297–9.

Google Scholar  

Cookenmaster C, Shebrain S, Vos D, et al. Gender perception bias of operative autonomy evaluations among residents and faculty in general surgery training. Am J Surg. 2021;221(3):515–20. https://doi.org/10.1016/j.amjsurg.2020.11.016 .

Olumolade OO, Rollins PD, Daignault-Newton S, et al. Closing the Gap: Evaluation of Gender Disparities in Urology Resident Operative Autonomy and Performance.Journal of Surgical Education.2022;79 (2), 524–530. doi.org/10.1016/j.jsurg.2021.10.010.

Chen JX, Chang EH, Deng F, et al. Autonomy in the Operating Room: A Multicenter Study of Gender Disparities During Surgical Training. Journal of Graduate Medical Education. 2021;13(5), 666–672. doi: 10.4300/JGME-D-21-00217.1.

Meyerson SL, Sternbach JM, Zwischenberger JB, & Bender EM. The Effect of Gender on Resident Autonomy in the Operating room. Journal of Surgical Education. 2017. 74(6), e111–e118. doi.org/10.1016/j.jsurg.2017.06.014.

Hoops H, Heston A, Dewey E, et al. Resident autonomy in the operating room: Does gender matter? The AmericanJournalofSurgery. 2019; 217(2), 301–305. doi.org/10.1016/j.amjsurg.2018.12.023.

Padilla EP, Stahl CC, Jung SA, et al. Gender Differences in Entrustable Professional Activity Evaluations of General Surgery Residents. Annals of Surgery. 2022;275 (2), 222–229. doi:10.1097/SLA.0000000000004905.

Cooney CM, Aravind P, Hultman CS, et al. An Analysis of Gender Bias in Plastic Surgery Resident Assessment. Journal of Graduate Medical Education. 2021;13 (4), 500–506. doi:10.4300/JGME-D-20-01394.1.

Roshan A, Farooq A, Acai A, et al. The effect of gender dyads on the quality of narrative assessments of general surgery trainees. The American Journal of Surgery. 2022; 224 (1A), 179–184. doi.org/10.1016/j.amjsurg.2021.12.001.

Gong D, Winn BJ, Beal CJ, et al. Gender Differences in Case Volume Among Ophthalmology Residents. Archives of Ophthalmology. 2019;137 (9), 1015–1020. doi:10.1001/jamaophthalmol.2019.2427.

Foley KE, Izquierdo KM, von Muchow MG, et al. Colon and Rectal Surgery Robotic Training Programs: An Evaluation of Gender Disparities. Diseases of the Colon and Rectum. 2020; 63(7), 974–979. doi.org/10.1097/DCR.0000000000001625.

Ali A, Subhi Y, Ringsted C et al. Gender differences in the acquisition of surgical skills: a systematic review. Surgical Endoscopy. 2015;29 (11), 3065–3073. doi:10.1007/s00464-015-4092-2.

Eruchalu CN, He K, Etheridge JC, et al. Gender and Racial/Ethnic Disparities in Operative Volumes of Graduating General Surgery Residents.The Journal of Surgical Research. 2022; 279, 104–112. doi.org/10.1016/j.jss.2022.05.020.

Antonoff MB, Feldman H, Luc JGY, et al. Gender Bias in the Evaluation of Surgical Performance: Results of a Prospective Randomized Trial. Annals of Surgery. 2023;277 (2), 206–213. doi:10.1097/SLA.0000000000005015.

Dill-Macky A, Hsu C, Neumayer LA, et al. The Role of Implicit Bias in Surgical Resident Evaluations. Journal of Surgical Education. 2022;79 (3), 761–768. doi:10.1016/j.jsurg.2021.12.003.

Skjold-Ødegaard B, Ersdal HL, Assmus J et al. Comparison of Performance Score for Female and Male Residents in General Surgery Doing Supervised Real-Life Laparoscopic Appendectomy: Is There a Norse Shield-Maiden Effect? World Journal of Surgery. 2021;45 (4), 997–1005. doi:10.1007/s00268-020-05921-4.

Leape CP, Hawken JB, Geng X, et al. An investigation into gender bias in the evaluation of orthopedic trainee arthroscopic skills. Journal of Shoulder and Elbow Surgery. 2022;31 (11), 2402–2409. doi:10.1016/j.jse.2022.05.024.

Vogt VY, Givens VM, Keathley CA, et al. Is a resident’s score on a videotaped objective structured assessment of technical skills affected by revealing the resident’s identity? American Journal of Obstetrics and Gynecology. 2023;189 (3), 688–691. doi:10.1067/S0002-9378(03)00887-1.

Fjørtoft K, Konge L, Christensen J et al. Overcoming Gender Bias in Assessment of Surgical Skills. Journal of Surgical Education. 2022;79 (3), 753–760. doi:10.1016/j.jsurg.2022.01.006.

Grantcharov TP, Bardram L, Funch-Jensen P, et al. Impact of Hand Dominance, Gender, and Experience with Computer Games on Performance in Virtual Reality Laparoscopy. Surgical Endoscopy 2003;17 (7): 1082–85.

Rosser Jr JC, Rosser LE & Savalgi RS. Objective Evaluation of a Laparoscopic Surgical Skill Program for Residents and Senior Surgeons. Archives of Surgery. 1998; 133 (6): 657–61.

White MT & Welch K. Does gender predict performance of novices undergoing Fundamentals of Laparoscopic Surgery (FLS) training? The American Journal of Surgery. 2012;203 (3), 397–400. doi:10.1016/j.amjsurg.2011.09.020.

Nugent E, Joyce C, Perez-Abadia G, et al. Factors influencing microsurgical skill acquisition during a dedicated training course. Microsurgery. 2012;32 (8), 649–656. doi:10.1002/micr.22047.

Milam LA, Cohen GL, Mueller C et al. Stereotype threat and working memory among surgical residents. The American Journal of Surgery. 2018;216 (4), 824–829. doi:10.1016/j.amjsurg.2018.07.064.

Myers SP, Dasari M, Brown JB, et al. Effects of Gender Bias and Stereotypes in Surgical Training: A Randomized Clinical Trial. JAMA Surgery. 2020; 155(7), 552–560. doi.org/10.1001/jamasurg.2020.1127.

Yeo HL, Patrick TD, Jialin M, et al. Association of Demographic and Program Factors With American Board of Surgery Qualifying and Certifying Examinations Pass Rates. JAMA Surgery 2020; 155 (1): 22–30. doi:0.1001/jamasurg.2019.4081.

Foster N, Meghan P, Bettger JP, et al. Objective Test Scores Throughout Orthopedic Surgery Residency Suggest Disparities in Training Experience. Journal of Surgical Education 2021;78 (5): 1400–1405. doi:10.1016/j.jsurg.2021.01.003.

Robinson DBT, Hopkins L, Brown C, et al. Prognostic Significance of Ethnicity on Differential Attainment in Core Surgical Training (CST). Journal of the American College of Surgeons. 2019;229 (4), e191. doi:10.1016/j.jamcollsurg.2019.08.1254.

Roe V, Patterson F, Kerrin M, et al. What supported your success in training? A qualitative exploration of the factors associated with an absence of an ethnic attainment gap in post-graduate specialty training. General Medical Council. 2019. https://www.gmc-uk.org/-/media/documents/gmc-da-final-report-success-factors-in-training-211119_pdf-80914221.pdf [Last accessed 28/12/23].

Royal College of Ophthalmologists. Data on Differential attainment in ophthalmology and monitoring equality, diversity, and inclusion: Recommendations to the RCOphth. London, Royal College of Ophthalmologists. 2022. https://www.rcophth.ac.uk/wp-content/uploads/2023/01/Differential-Attainment-Report-2022.pdf [Last accessed 28/12/23].

Tiffin PA, Orr J, Paton LW, et al. UK nationals who received their medical degrees abroad: selection into, and subsequent performance in postgraduate training: a national data linkage study. BMJ Open. 2018;8:e023060. doi: 10.1136/bmjopen-2018-023060.

Woolf K, Rich A, Viney R, et al. Perceived causes of differential attainment in UK postgraduate medical training: a national qualitative study. BMJ Open. 2016;6 (11), e013429. doi:10.1136/bmjopen-2016-013429.

Brooks JT, Porter SE, Middleton KK, et al. The Majority of Black Orthopaedic Surgeons Report Experiencing Racial Microaggressions During Their Residency Training. Clinical Orthopaedics and Related Research. 2023;481 (4), 675–686. doi:10.1097/CORR.0000000000002455.

Ellis R, Cleland J, Scrimgeour D, et al. The impact of disability on performance in a high-stakes postgraduate surgical examination: a retrospective cohort study. Journal of the Royal Society of Medicine. 2022;115 (2), 58–68. doi:10.1177/01410768211032573.

Royal College of Obstetricians & Gynaecologists. RCOGWorkforceReport2022. Available at: https://www.rcog.org.uk/media/fdtlufuh/workforce-report-july-2022-update.pdf [Last accessed 28/12/23].

Crenshaw KW. On Intersectionality: Essential Writings. Faculty Books. 2017; 255.

Brennan CM & Harrison W. The Dyslexic Surgeon. The Bulletin of the Royal College of Surgeons of England. 2020;102 (3): 72–75. doi:10.1308/rcsbull.2020.72.

Toman L. Navigating medical culture and LGBTQ identity. Clinical Teacher. 2019;16: 335–338. doi:10.1111/tct.13078.

Torales J, Castaldelli-Maia JM & Ventriglio A. LGBT + medical students and disclosure of their sexual orientation: more than in and out of the closet. International Review of Psychiatry. 2022;34:3–4, 402–406. doi:10.1080/09540261.2022.2101881.

Guda VA & Kundu RV. India’s Fair Skin Phenomena. SKINmed. 2021;19(3), 177–178.

Massey D & Martin JA. The NIS skin color scale. Princeton University Press. 2003.

Intercollegiate Committee for Basic Surgical Examinations.AccessArrangementsandReasonableAdjustmentsPolicyforCandidateswithaDisabilityorSpecificLearningdifficulty. 2020. https://www.intercollegiatemrcsexams.org.uk/-/media/files/imrcs/mrcs/mrcs-regulations/access-arrangements-and-reasonable-adjustments-january-2020.pdf [Last accessed 28/12/23].

Regan de Bere S, Nunn S & Nasser M. Understanding differential attainment across medical training pathways: A rapid review of the literature. General Medical Council. 2015. https://www.gmc-uk.org/-/media/documents/gmc-understanding-differential-attainment_pdf-63533431.pdf [Last accessed 28/12/23].

Unwin E, Woolf K, Dacre J, et al. Sex Differences in Fitness to Practise Test Scores: A Cohort Study of GPs. The British Journal of General Practice: The Journal of the Royal College of General Practitioners. 2019; 69 (681): e287–93. doi:10.3399/bjgp19X701789.

Pattinson J, Blow C, Sinha B et al. Exploring Reasons for Differences in Performance between UK and International Medical Graduates in the Membership of the Royal College of General Practitioners Applied Knowledge Test: A Cognitive Interview Study. BMJ Open. 2019;9 (5): e030341. doi:10.1136/bmjopen-2019-030341.

Andrews J, Chartash D & Hay S. Gender Bias in Resident Evaluations: Natural Language Processing and Competency Evaluation. Medical Education. 2021;55 (12): 1383–87. doi:10.1111/medu.14593.

Yeates P, Woolf K, Benbow E, et al. A Randomised Trial of the Influence of Racial Stereotype Bias on Examiners’ Scores, Feedback and Recollections in Undergraduate Clinical Exams. BMC Medicine 2017;15 (1): 179. doi:10.1186/s12916-017-0943-0.

Woolf K, McManus IC, Potts HWW et al. The Mediators of Minority Ethnic Underperformance in Final Medical School Examinations. British Journal of Educational Psychology. 2013; 83 (1): 135–59. doi:10.1111/j.2044-8279.2011.02060.x.

Hope D, Adamson K, McManus IC, et al. Using Differential Item Functioning to Evaluate Potential Bias in a High Stakes Postgraduate Knowledge Based Assessment. BMC Medical Education. 2018;18 (1): 64. doi:10.1186/s12909-018-1143-0.

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Jones, R.L., Prusmetikul, S. & Whitehorn, S. Differential attainment in assessment of postgraduate surgical trainees: a scoping review. BMC Med Educ 24 , 597 (2024). https://doi.org/10.1186/s12909-024-05580-2

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Over the Memorial Day weekend, while most Americans were firing up their grills and enjoying a cold one, Yann LeCun , Meta’s chief AI scientist, and Elon Musk , the enigmatic CEO of Tesla and xAI , were engaged in a no-holds-barred digital dustup on X.com (formerly Twitter). This clash of the AI titans exposed some of the key fault lines in the fast-moving, hype-fueled field of artificial intelligence.

The online feud ignited on Sunday, May 26th when LeCun threw shade at Musk, who was promoting job openings at his new AI startup xAI. LeCun’s tweet was a masterclass in snark: “Join xAI if you can stand a boss who: claims that what you are working on will be solved next year (no pressure), claims that what you are working on will kill everyone and must be stopped or paused (yay, vacation for 6 months!), claims to want a ‘maximally rigorous pursuit of the truth’ but spews crazy-ass conspiracy theories on his own social platform.”

Join xAI if you can stand a boss who: – claims that what you are working on will be solved next year (no pressure). – claims that what you are working on will kill everyone and must be stopped or paused (yay, vacation for 6 months!). – claims to want a "maximally rigorous pursuit… — Yann LeCun (@ylecun) May 27, 2024

Musk, never one to back down from a fight, came out swinging. “What ‘science’ have you done in the past 5 years?” he posted, questioning LeCun’s recent contributions to the field. LeCun wasn’t about to let that one go: “Over 80 technical papers published since January 2022. What about you?”

What “science” have you done in the past 5 years? — Elon Musk (@elonmusk) May 27, 2024

The godfather of convolutional neural networks vs. The self-proclaimed savior of humanity

LeCun, 63, is a bonafide AI legend, one of the pioneers of deep learning , the groundbreaking technique that now powers everything from chatbots to self-driving cars. Back in 1989, as a researcher at Bell Labs, he co-authored a paper that introduced convolutional neural networks , a fundamental architecture of deep learning. “Every single driving assistance system today uses ConvNets,” LeCun posted, and he’s not wrong.

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Musk, 52, has had a more tumultuous relationship with the AI research community, despite his companies’ heavy reliance on the technology. His startup xAI has the lofty goal of building artificial general intelligence, or human-level AI—an ambition that many experts consider to be jumping the gun. Meanwhile, Tesla’s self-driving technology, which Musk has repeatedly hyped as being on the cusp of full autonomy, relies heavily on deep learning systems that were initially developed in academic labs like LeCun’s.

The Importance of Sharing Scientific Knowledge in the Age of Corporate Secrecy

“Technological marvels don’t just pop out of the vacuum,” LeCun posted. “They are built on years (sometimes decades) of scientific research that makes them possible. Research ideas and results are shared through technical papers. Without this sharing of scientific information, technological progress would slow to a crawl.”

To those who say 'these are *just* papers': One of these papers introduced convolutional neural networks (ConvNets) in 1989. Every single driving assistance system today uses ConvNets. That includes MobilEye (since 2014), Nvidia, Tesla, and just about everyone else.… — Yann LeCun (@ylecun) May 28, 2024

Musk, in true Muskian fashion, dismissed the importance of scientific publishing, claiming that Tesla doesn’t use convolutional neural networks much anymore in its self-driving stack. LeCun wasn’t buying it: “Curious to know how you could possibly do real-time camera image understanding in [Full Self-Driving] without ConvNets, TBH.”

Curious to know how you could possibly do real-time camera image understanding in FSD without ConvNets, TBH. — Yann LeCun (@ylecun) May 28, 2024

In an era where corporate secrecy around AI development is becoming the norm, exemplified by the tight-lipped labs of OpenAI and Google DeepMind , many experts still consider timely and transparent scientific publication to be essential to the long-term health of the field. Clem Delangue, co-founder of AI startup Hugging Face , summed it up nicely: “The scientists who publish their groundbreaking research openly are the cornerstone of technological progress & massively contribute to making the world a better place!”

I would pick @ylecun over @elonmusk every single day of the week. Despite getting much less $$, recognition & visibility than entrepreneurs, the scientists who publish their groundbreaking research openly are the cornerstone of technological progress & massively contribute to… — clem ? (@ClementDelangue) May 28, 2024

The future of AI: A tale of two visions

Both Meta and xAI have had eventful years in their quest for AI supremacy. Meta recently released a large language model called LLaMA 3 and is integrating similar technologies into its social apps like Instagram and WhatsApp, all while watching its market value slip away . Meanwhile, xAI announced a whopping $6 billion fundraise as Musk promises to build “artificial general intelligence,” though the details of his master plan remain fuzzy at best.

LeCun and Musk, two of the most influential figures in AI, clearly have divergent visions for the future of this transformative technology. But if this holiday weekend is any indication, the debates that will shape that future are increasingly playing out in the open, one tweet at a time. And we, for one, are here for it. Pass the popcorn.

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Cancer patients often do better with less intensive treatment, new research finds

FILE - In this May 25, 2017 file photo, chemotherapy drugs are administered to a patient at a hospital in Chapel Hill, N.C. Scaling back treatment in some cancers — ovarian, esophageal and Hodgkin lymphoma — can make life easier for patients without compromising outcomes, doctors reported at the American Society of Clinical Oncology annual meeting in early June 2024. (AP Photo/Gerry Broome, File)

FILE - In this May 25, 2017 file photo, chemotherapy drugs are administered to a patient at a hospital in Chapel Hill, N.C. Scaling back treatment in some cancers — ovarian, esophageal and Hodgkin lymphoma — can make life easier for patients without compromising outcomes, doctors reported at the American Society of Clinical Oncology annual meeting in early June 2024. (AP Photo/Gerry Broome, File)

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Scaling back treatment for three kinds of cancer can make life easier for patients without compromising outcomes, doctors reported at the world’s largest cancer conference.

It’s part of a long-term trend toward studying whether doing less — less surgery , less chemotherapy or less radiation — can help patients live longer and feel better. The latest studies involved ovarian and esophageal cancer and Hodgkin lymphoma.

Thirty years ago, cancer research was about doing more, not less. In one sobering example, women with advanced breast cancer were pushed to the brink of death with massive doses of chemotherapy and bone marrow transplants. The approach didn’t work any better than chemotherapy and patients suffered.

Now, in a quest to optimize cancer care, researchers are asking: “Do we need all that treatment that we have used in the past?”

It’s a question, “that should be asked over and over again,” said Dr. Tatjana Kolevska, medical director for the Kaiser Permanente National Cancer Excellence Program, who was not involved in the new research.

Often, doing less works because of improved drugs.

Cheng "Charlie" Saephan holds a check above his head after speaking during a news conference where it was revealed that he was one of the winners of the $1.3 billion Powerball jackpot at the Oregon Lottery headquarters on Monday, April 29, 2024, in Salem, Ore. (AP Photo/Jenny Kane)

“The good news is that cancer treatment is not only becoming more effective, it’s becoming easier to tolerate and associated with less short-term and long-term complications,” said Dr. William G. Nelson of Johns Hopkins School of Medicine, who was also not involved in the new research.

Studies demonstrating the trend were discussed over the weekend at an American Society of Clinical Oncology conference in Chicago. Here are the highlights:


French researchers found that it’s safe to avoid removing lymph nodes that appear healthy during surgery for advanced ovarian cancer. The study compared the results for 379 patients — half had their lymph nodes removed and half did not. After nine years, there was no difference in how long the patients lived and those with less-extreme surgery had fewer complications, such as the need for blood transfusions. The research was funded by the National Institute of Cancer in France.


This German study looked at 438 people with a type of cancer of the esophagus that can be treated with surgery. Half received a common treatment plan that included chemotherapy and surgery on the esophagus, the tube that carries food from the throat to the stomach. Half got another approach that includes radiation too. Both techniques are considered standard. Which one patients get can depend on where they get treatment.

After three years, 57% of those who got chemo and surgery were alive, compared to 51% of those who got chemo, surgery and radiation. The German Research Foundation funded the study.


A comparison of two chemotherapy regimens for advanced Hodgkin lymphoma found the less intensive treatment was more effective for the blood cancer and caused fewer side effects.

After four years, the less harsh chemo kept the disease in check in 94% of people, compared to 91% of those who had the more intense treatment. The trial included 1,482 people in nine countries — Germany, Austria, Switzerland, the Netherlands, Denmark, Sweden, Norway, Australia and New Zealand — and was funded by Takeda Oncology, the maker of one of the drugs used in the gentler chemo that was studied.

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.

review article and research article difference

What’s the difference between vegan and vegetarian?

"a 2023 review looked at the health effects of vegetarian and vegan diets from two types of study", by katherine livingstone.

This article was originally published on The Conversation .

Vegan and vegetarian diets are plant-based diets . Both include plant foods, such as fruits, vegetables, legumes and whole grains.

But there are important differences, and knowing what you can and can't eat when it comes to a vegan and vegetarian diet can be confusing.

So, what's the main difference?

What's a vegan diet?

A vegan diet is an entirely plant-based diet. It doesn't include any meat and animal products. So, no meat, poultry, fish, seafood, eggs, dairy or honey.

What's a vegetarian diet?

A vegetarian diet is a plant-based diet that generally excludes meat, poultry, fish and seafood, but can include animal products. So, unlike a vegan diet, a vegetarian diet can include eggs, dairy and honey.

But you may be wondering why you've heard of vegetarians who eat fish, vegetarians who don't eat eggs, vegetarians who don't eat dairy, and even vegetarians who eat some meat. Well, it's because there are variations on a vegetarian diet:

a lacto-ovo vegetarian diet excludes meat, poultry, fish and seafood, but includes eggs, dairy and honey

an ovo-vegetarian diet excludes meat, poultry, fish, seafood and dairy, but includes eggs and honey

a lacto-vegetarian diet excludes meat, poultry, fish, seafood and eggs, but includes dairy and honey

a pescatarian diet excludes meat and poultry, but includes eggs, dairy, honey, fish and seafood

a flexitarian , or semi-vegetarian diet, includes eggs, dairy and honey and may include small amounts of meat, poultry, fish and seafood.

review article and research article difference

Are these diets healthy?

A 2023 review looked at the health effects of vegetarian and vegan diets from two types of study.

Observational studies followed people over the years to see how their diets were linked to their health. In these studies, eating a vegetarian diet was associated with a lower risk of developing cardiovascular disease (such as heart disease or a stroke), diabetes, hypertension (high blood pressure), dementia and cancer.

For example, in a study of 44,561 participants, the risk of heart disease was 32% lower in vegetarians than non-vegetarians after an average follow-up of nearly 12 years.

Further evidence came from randomized controlled trials. These instruct study participants to eat a specific diet for a specific period of time and monitor their health throughout. These studies showed eating a vegetarian or vegan diet led to reductions in weight, blood pressure, and levels of unhealthy cholesterol.

For example, one analysis combined data from seven randomized controlled trials. This so-called meta-analysis included data from 311 participants. It showed eating a vegetarian diet was associated with a systolic blood pressure (the first number in your blood pressure reading) an average 5 mmHg lower compared with non-vegetarian diets.

It seems vegetarian diets are more likely to be healthier, across a number of measures.

For example, a 2022 meta-analysis combined the results of several observational studies. It concluded a vegetarian diet, rather than vegan diet, was recommended to prevent heart disease.

There is also evidence vegans are more likely to have bone fractures than vegetarians. This could be partly due to a lower body-mass index and a lower intake of nutrients such as calcium, vitamin D and protein.

But it can be about more than just food

Many vegans, where possible, do not use products that directly or indirectly involve using animals.

So vegans would not wear leather, wool or silk clothing, for example. And they would not use soaps or candles made from beeswax, or use products tested on animals.

The motivation for following a vegan or vegetarian diet can vary from person to person. Common motivations include health, environmental, ethical, religious or economic reasons.

And for many people who follow a vegan or vegetarian diet, this forms a central part of their identity .


So, should I adopt a vegan or vegetarian diet?

If you are thinking about a vegan or vegetarian diet, here are some things to consider:

eating more plant foods does not automatically mean you are eating a healthier diet. Hot chips, biscuits and soft drinks can all be vegan or vegetarian foods. And many plant-based alternatives , such as plant-based sausages, can be high in added salt

meeting the nutrient intake targets for vitamin B12, iron, calcium, and iodine requires more careful planning while on a vegan or vegetarian diet. This is because meat, seafood and animal products are good sources of these vitamins and minerals

eating a plant-based diet doesn't necessarily mean excluding all meat and animal products. A healthy flexitarian diet prioritizes eating more whole plant-foods, such as vegetables and beans, and less processed meat, such as bacon and sausages

the Australian Dietary Guidelines recommend eating a wide variety of foods from the five food groups (fruit, vegetables, cereals, lean meat and/or their alternatives and reduced-fat dairy products and/or their alternatives). So if you are eating animal products, choose lean, reduced-fat meats and dairy products and limit processed meats.

Katherine Livingstone , NHMRC Emerging Leadership Fellow and Senior Research Fellow at the Institute for Physical Activity and Nutrition, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article .

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