Writing a review paper: A simple task or an impeccable skill?

The perception that writing a review article is simple is not very uncommon. Most people believe that a review article is just a straightforward process of creating a comprehensive manuscript. Familiarity with the topic, lack of understanding of the research process, perceiving the review article as just a summation of the literature, and misunderstanding the actual purpose of the review are common delusions.

Contrary to this belief, writing review articles involves synthesizing existing research and knowledge on a particular topic and requires clear objectives, extensive research, critical thinking, a deep understanding of the topic, and clear organizational and writing skills. There are many forms of recognized review articles as “systematic reviews and meta-analysis,” “umbrella reviews,” “rapid reviews or rapid literature reviews or quick scoping reviews,” “narrative reviews” (or “literature scan”), “focused articles,” “scoping reviews” or “invited reviews” or “state-of-theart review,” “over-view,” and “critical review.”^[1-3] “Systematic reviews” are qualitative secondary original research having a rigorous and structured approach to reviewing literature with a focus on methodology and minimizing bias, whereas “meta-analysis” includes statistical analysis of results of multiple studies combined for quantitative assessment of the review protocol. “Umbrella reviews”, also known as “overviews of reviews,” “reviews of reviews,” “summaries of systematic reviews,” or “synthesis of reviews”, are new methodological concepts for synthesizing the evidence from systematic reviews.^[2]

In the Evidence-Based Medicine/Dentistry pyramid, systematic reviews and meta-analyses are considered at the top and are considered secondary original research. At present, prospective registration of systematic reviews before its commencement is of paramount importance. This ensures transparency, reduces bias, improves research quality, promotes accountability, supports evidence synthesis, avoids duplication of efforts, encourages collaborations, facilitates long-term records, public access, and public dissemination, discloses conflicts of interest, defines the standard approach, guidance adherence for patient care, enables update, facilitates publication, facilitates recognition, decision-making, and policy development for the population at large. PROSPERO is a free International Database of Prospectively Registered Systematic Review in any field affecting health outcomes. As per the information on their website, “PROSPERO accepts registration for systematic reviews, rapid reviews, and umbrella reviews.”^[4] Besides PROSPERO, systematic reviews can also be registered in the Registry of Systematic Reviews/Meta-analyses in Research Registry, INPLASY, Cochrane, Joanna Briggs Institute, the Campbell Collaboration, Open Science Framework, or Figshare.^[5] Training in systematic review reporting and writing equips researchers with the necessary skills to conduct high-quality reviews that are reproducible, credible, and valuable to the scientific community. In fact, secondary original research, systematic reviews, and meta-analysis can be seen as important skill-building opportunities for early career researchers.

“Narrative”, “traditional reviews”, or “literature scan,” on the other hand, are more flexible than systematic reviews, offering a general summary and commentary of the literature without strict methodological constraints. “Scoping reviews” are systematic overviews with a broader focus, usually to map the literature on a topic and identify key concepts. “Critical reviews” generally demonstrate that the author(s) have extensively researched the literature and critically evaluated its quality to identify conceptual endeavours to substantiate existing or derive new hypotheses. “Overviews” are chronological, conceptual, thematic analyses and summaries of medical literature that attempt to survey the literature and describe its characteristics.^[3] Journals do accept literature reviews, overviews, rapid reviews, state-of-theart-reviews, position papers, opinion articles, and focused reviews having censorious compilation and discussion of scientific results through comprehensive search strategy and critical analysis. Often, these papers provide complete background knowledge while evaluating and formulating practical recommendations.^[6] However, narrative reviews or overviews, if not critically analyzed, may have a component of bias, and the reader can hear the narrator’s voice as opposed to the systematic reviews, which follow a preset format that allows no room for bias.

The International Committee for Medical Journal Editors (ICMJE) recommend the use of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines for publishing review articles.^[7] Besides PRISMA, authors can follow the Search, Appraisal, Synthesis, and Analysis (SALSA) framework for writing review articles.^[3,8] Readers may refer to Enhancing the Quality and Transparency of Health Research (EQUATOR) Network for guidelines to report various types of studies.^[9] Henceforth, while adhering to the ICMJE guidelines, the Asian Journal of Oral Health and Allied Sciences encourages the submission of systematic reviews and meta-analyses that are written according to PRISMA or SALSA guidelines. Systematic reviews and meta-analysis-based prospective protocol registries will be given preference. The standard format and template for the prospective protocol registry available on PROSPERO and other systematic review trial registry websites can be referred to for detailed guidelines.