CAse-BAsed REview sTandards (CABARET): Considerations for Authors, Reviewers, and Editors

Abstract

The publication landscape for case reports has undergone a significant shift, with many high-impact journals deprioritizing or ceasing their publication altogether. This trend has led to the emergence of case-based reviews as an alternative to traditional case reports. Several factors drive this shift. Case-based reviews offer a more comprehensive synthesis of the literature compared to single case reports. They employ systematic search methodologies, reducing the risk of excluding relevant data, and providing robust evidence. From a publisher’s perspective, case-based reviews have a greater potential for citation. While recommendations exist for writing traditional case reports, such as the CAse REports (CARE) guidelines, there is a lack of published recommendations for composing case-based reviews. This review aims to address this gap by providing guidance on drafting high-quality case-based reviews.

Graphical Abstract

INTRODUCTION

In recent years, numerous high-impact factor journals have deprioritized the publication of case reports, with some ceasing such publications altogether. However, a notable trend has emerged wherein certain journals have shifted towards the dissemination of case-based reviews as an alternative to traditional case reports.1 Several factors underlie this trend. One contributing factor is the enhanced comprehensiveness of case-based reviews.

Unlike individual case reports, case-based reviews offer a more comprehensive synthesis of the existing literature on a given topic. As such, case-based reviews are expected to utilize systematic and rigorous search methodologies to identify and include all relevant cases and data. This approach mitigates the risk of overlooking pertinent information, ultimately providing readers with a more robust and evidence-based analysis of the subject matter. Moreover, from the perspective of academic publishers, case-based reviews tend to garner more citations compared to single case reports, making them a more valuable contribution to the scientific literature.

While there are several publications outlining methodologies for drafting case reports,1,2,3,4,5,6,7,8 and dedicated guidelines like the 13-item CAse REports (CARE) checklist to ensure the fulfillment of requirements in published case reports,9 there is a notable lack of published recommendations or guidelines specifically for composing case-based reviews. Considering this gap in the literature, the present manuscript aims to provide recommendations and guidelines for the composition of high-quality case-based reviews. By establishing a structured framework, these recommendations will serve as a definitive reference for authors seeking to contribute to the growing body of case-based review literature, as well as to set standards for peer reviewers and editors evaluating case-based reviews.

SEARCH STRATEGY

A systematic search of scholarly databases including PubMed/MEDLINE, Web of Science, and Scopus was undertaken to identify related literature. Selection criteria focused on English-language articles related to the subject matter of scientific writing in case reports and narrative reviews. Emphasis was placed on articles published within the last 10 years. Additionally, reference lists of included articles in the narrative review were scrutinized to find other relevant publications. Recommendations for writing narrative reviews were followed.10

SUGGESTED SECTIONS FOR THE MAIN TEXT OF A CASE-BASED REVIEW

Prior to the main text, a concise yet informative title, an abstract, and relevant keywords should be provided. The title should clearly depict the topic of the case-based review and conclude with the phrase “case-based review.” The abstract can follow an unstructured format unless otherwise specified by the target journal's guidelines. For the main body, a recommended structure includes the following sections: an introduction providing context and background on the subject matter, a detailed case presentation describing the relevant case(s), an outline of the systematic search methodology used to identify and select pertinent literature, a literature review synthesizing and critically analyzing the relevant published cases and studies, a discussion interpreting the findings, highlighting key implications, and addressing limitations, and finally, conclusions and future perspectives summarizing the main conclusions and suggesting potential areas for future research.

Introduction of the subject matter

Introduction to the topic is an essential part of a case-based review. This section is recommended to be brief while remaining sufficiently explanatory enough at the same time. The concise background should reference the relevant medical literature.9 The novelty of the article/related case should be explicitly outlined. Novelty is an important crucial element since it captivates readers while facilitating their acquisition of knowledge via the examination of unique experiences shared by others.

While case-based reviews on emerging diseases or new pharmaceutical agents naturally possess novelty, distinctive elements can also arise from unique circumstances, uncommon resolutions, complex combinations of comorbidities, or human factors encapsulated within a given case.4 After describing the novelty or distinctive aspect, the main objective of the case-based review should be clearly stated in a concise sentence at the end of the introduction.

Exposition of the case(s)

The “case presentation” section should provide a factual and modest description of the case(s) without speculating on the underlying disease mechanisms or treatment/management. Following the CARE guidelines, authors should include: 1) Demographics (age, gender, etc.) of the patient(s), 2) Primary symptoms and concerns, 3) Detailed medical history, including comorbidities, medications used for concurrent conditions, relevant past interventions (e.g., surgery) and their respective outcomes, and 4) Family and psychosocial history of the patient(s).

The case presentation should focus on clearly outlining the clinical details and chronology of events, avoiding premature interpretations or explanations at this stage. Following this, the document should succinctly present: 1) clinical findings, 2) diagnostic evaluations and their findings, 3) the diagnosis (including rule-out diagnoses), 4) management/therapeutic intervention (e.g. type, dose, duration), and 5) outcomes and follow-up findings.9,11 Follow-up findings should be given from both physician and patient perspective.4 Adverse events/reactions, if any, should also be stated clearly.12 At that stage, adding a timeline would be of great value.

At the end of the case presentation section, authors should provide concise information regarding patient consent. It should be confirmed that written informed consent was obtained from the relevant patient(s) or, where applicable, from their parent, guardian, or legal representative for the publication of the case details and any accompanying images. A clear example statement would be: “Written informed consent was obtained from the patient(s) for the publication of this case-based review and any accompanying images.”13 Depending on the journal’s guidelines and local institutional policies, obtaining approval from an ethics committee or institutional review board may be necessary.8 Case-based reviews reporting one to three patients with no hypothesis testing may be exempted from ethical approval.14 Special care must be taken to ensure that all potential patient identifiers have been thoroughly removed or concealed from every aspect of the manuscript to maintain patient confidentiality.1

Delineation of the comprehensive search methodology employed

It is crucial to explain the details of the search methodology employed in the case-based review. The essential elements of a literature search are 1) asking the correct question, 2) choosing appropriate databases, 3) identifying keywords, and 4) refining the search. The most important aspect of doing a successful search is to ask the proper questions which can be answered. If the inquiry is too broad, the search will return more results than can be feasibly sifted through. The most appropriate database should be chosen to begin a literature search. Thereafter, the search should be expanded through other databases. In other words, it is advisable to use 2–3 databases (e.g. MEDLINE, Web of Science, and Scopus) in a literature search. It would be more inclusive if the authors perform searches through the Directory of Open Access Journals (DOAJ) and specialist databases such as Chemical Abstracts Service (CAS), PsycINFO and Cumulative index to Nursing and Allied Health Literature (CINAHL).15,16 Key phrases from the inquiry are identified and entered into the database's search box. PubMed uses a regulated vocabulary known as Medical Subject Headings (MeSH) to index journal articles. It uses “automatic term mapping” to find MeSH keywords when searching. These words are organized in a hierarchy. Narrower terms nested under wider ones. The search can be refined as needed by combining keywords and/or utilizing the database’s restricting choices.17 It is also advisable to give details on exclusion and inclusion criteria (language, publication time, article type, etc.). Search strategy can be presented via a flowchart for a better understanding.18

Review of the pertinent literature

Case-based reviews are expected to provide a comprehensive synthesis of the relevant literature obtained through systematic database searches. This literature review section should synthesize previously published studies and cases related to the subject matter, delineating similarities and distinctions among them to offer a comparative discussion for readers. Authors can further expound on the novelty or distinctive aspects of the presented case(s) or intervention in this section.

The use of a table to concisely summarize key details from earlier reports is highly recommended, as it allows for a succinct presentation of the existing literature corpus.19 This tabular approach prevents the need for overly lengthy explanations within the “literature review” section itself. Overall, the goal is to offer a well-organized and systematic synthesis of the pertinent literature, highlighting how the current case-based review contributes to the existing body of knowledge.

Discussion

The discussion section could commence by delineating the primary components of the case presented. Presenting/chief symptoms, diagnostic findings, diagnosis, therapeutic interventions/outcomes can be rearticulated in one or two sentences. Thereafter, the discussion may involve an exploration of underlying pathophysiological mechanisms and other scientifically important details related to the clinical trajectory of the patient’s condition.

An additional critical element within this section involves the discussion of differential diagnoses, wherein elucidation of the rationale leading to the ultimate diagnosis is vital.3 In the case report section, a concise elucidation of the differential diagnoses should be provided. However, within this section, a comprehensive discussion may be undertaken, delving into the differences and likenesses between potential differential diagnoses and the requisite approach for arriving at a definitive diagnosis.

The discussion section should explore the case’s significance for the medical community. This includes evaluating its contribution to current scientific understanding and its potential application in clinical practice. Additionally, the possibility of this report stimulating further research that could influence clinical protocols should be considered.3

By critically analyzing both the strengths and limitations of the manuscript in the discussion section, researchers can offer a balanced perspective on the reliability and generalizability of their findings.9 This evaluative commentary strengthens the scientific rigor of the study by demonstrating transparency and a comprehensive understanding of the research.

Conclusions and future perspectives

The conclusion should succinctly summarize the key takeaways. Limiting it to a concise paragraph is recommended. A crucial aspect of scholarly communication is proposing future directions. This section should highlight potential research avenues by identifying gaps in the literature and suggesting new research ideas. This fosters further inquiry and advances scientific knowledge.

VISUAL PRESENTATIONS IN CASE-BASED REVIEWS

Visual representations are essential in case-based reviews for illustrating inspection findings and diagnostic imaging studies. Providing a high-resolution image is crucial to ensure clarity and understanding. The image should be devoid of any patient-specific personal information, such as their name, to maintain privacy and confidentiality.

When presenting multiple cases that illustrate a particular clinical scenario, the inclusion of a picture gallery can greatly enhance the case-based review. Visual representations, such as photographs, imaging studies, or other relevant figures, can provide readers with a clearer understanding of the clinical manifestations, diagnostic findings, or interventions described in the cases. Providing visual aids (tables, images, figures) would not only attract attention but also pave the way for a better description of the case.20 Supplementary videos that enhance the reader's comprehension of the case can be uploaded, when appropriate.3 Incorporating an infographic into a case-based review is also a valuable option particularly when discussing the underlying mechanisms of a clinical condition. Infographics boost engagement, improve memory retention, and enhance comprehension.20

It is recommended to use table presentations when presenting the results of similar case reports found in the literature. Table presentations can also effectively convey details of the case, including the results of laboratory findings.21 Utilizing a table or figure presentation is recommended for depicting important dates and times in the case, structured as a timeline of the clinical course.9,21,22

A well-curated picture gallery allows authors to efficiently convey key details that may be challenging to articulate through text alone. Additionally, a picture gallery can serve as a valuable comparative tool, enabling readers to discern similarities and differences among the cases more readily. As the review progresses to synthesize the broader literature on the topic, the picture gallery can act as a reference point, helping readers connect the specific cases to the broader context provided by the published literature while improving the clarity, impact, and educational value of a case-based review that presents multiple clinical cases.23

DISCUSSION AND FUTURE PERSPECTIVES

The concept of a “case-based review” has undergone greater explication, leading to its recognition as a distinct article type in various prestigious journals. MeSH terms/heading such as “Review of Reported Cases,” “Case-base Studies,” and “Case Reports,” are readily available. “Case Reports [Publication Type]” and “Review [Publication Type]” were introduced in 2008 (1996).24,25 Most recently, in 2023, “Case Reports as Topic” was introduced for “clinical presentations that may be followed by evaluative studies that eventually lead to a diagnosis.”26 However, the specific term “case-based review” is absent from the MeSH browser. Accordingly, it is advisable to incorporate this term into the MeSH browser to facilitate indexing.

Several reputable journals (e.g. Rheumatology International, Clinical Rheumatology, Seminars in Neurology, World Journal of Urology) provide opportunities for publishing case-based reviews. Case-based reviews offer readers a blend of a case report and literature review. Through table presentations of past publications on the subject, graphical representations detailing the clinical course of the reported patient(s), and illustrations depicting the pathophysiological context of the relevant clinical condition, case-based reviews serve as invaluable resources for readers and aspiring authors alike. Review papers have high citability, even 3 times more than that of original papers. Miranda and Garcia-Carpintero27 stated that a 20% reviews can increase 40–80% the average citations of an author. On the contrary, editorials, letters to editors, and case studies typically receive limited citation.27 In this regard, case-based reviews are also expected to get higher number of citations for journals and authors. Given the potentially higher visibility of case-based reviews, the quality of such publications is of great value. Authors and editors should meticulously fulfill their essential roles in maximizing the usefulness of the literature review for the scientific and biomedical community.28 The manuscripts should be carefully evaluated during the peer review and editing process in terms of the principles of scientific writing, clarity, and potential plagiarism.29,30,31 Within this context, the current guide also aimed to raise awareness among authors, reviewers, and editors by developing standards for writing case-based reviews.

Reporting guidelines have been established for various study designs, encompassing observational studies, randomized controlled trials, case reports and systematic reviews/meta-analyses among them.9,32,33,34 For instance, the CARE guidelines were developed for case studies and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was established for systematic reviews and meta-analyses.9,34 The comparison of CAse-BAsed REview sTandards (CABARET) and CARE recommendations based on manuscript sections are depicted in Table 1. A checklist for CABARET is provided as a supplementary file (Supplementary Data 1). While the current narrative review endeavored to provide guidance for prospective authors intending to compose case-based reviews, there still exists a necessity for the formulation of a dedicated guideline tailored to the reporting of case-based reviews.

Table 1. Comparison of case-based reviews and case reports based on the CABARET and CARE recommendations, respectively.

Sections	CABARET	CARE
Abstract	Similar	Similar
Introduction	More than one or two paragraphs	One or two paragraphs
Presentation of the case(s)	Similar	Similar
Search methodology	It is advised to provide a “comprehensive search strategy” section	Providing the details of search methodology is not recommended
Literature review	It is advised to provide a comprehensive “literature review” section	It is advised to review relevant medical literature in the discussion section
Discussion	Similar	Similar
Conclusion	It is advised to provide a “conclusions and future perspectives” section	It is advised to provide the conclusions as a last paragraph of the discussion section

CONCLUDING REMARKS

The decline of traditional case reports in high-impact journals has paved the way for case-based reviews as a valuable alternative. These reviews offer a more comprehensive and evidence-based approach by synthesizing existing literature alongside a specific case. This not only reduces the risk of bias but also provides a richer context for understanding the presented case.

However, the lack of established guidelines for case-based reviews can hinder their quality and impact. This review has strived to address this gap by outlining key steps for crafting high-quality case-based reviews. By following these recommendations, researchers can effectively utilize this approach to disseminate valuable clinical insights and contribute to the advancement of medical knowledge.

SUPPLEMENTARY MATERIAL

Supplementary Data 1

Checklist for CAse-BAsed REview sTandards (CABARET)