No doubt you are already using synthesized information to keep abreast of changes in optometric and ophthalmic practices, but navigating these resources, as they are constantly evolving, can be disorienting to practitioners. You can better understand how review articles can help you in your evidence-based practice by knowing some of their core characteristics and how these differ among review types. This article briefly outlines three main categories of review articles typically used to synthesis studies in healthcare; narrative reviews, scoping reviews and systematic reviews.
Reviews are a method of knowledge synthesis1 with the core characteristics of “collecting, evaluating and presenting the available research evidence” 2 . However, the major distinction between review types is the rigor applied to their methodology. This rigor increases as you move from narrative, to scoping, to systematic review.
See the following table (PDF) for a checklist of characteristics: narrative reviews, scoping reviews, and systematic reviews
Narrative reviews
Narrative reviews, also known as literature reviews, are summaries of the current state of knowledge on a specific topic. They typically involve identifying a topic or hypothesis, collecting the literature, critiquing the evidence and summarizing the authors views. Narrative reviews are valuable in identifying trends, shifts, and gaps in an area of research.
Scoping reviews
Scoping reviews are commonly used as a way to comprehensively map the extent, nature, and themes in an area of research and “may be particularly relevant to disciplines with emerging evidence” 3. They are distinct from narrative reviews by using the methods section to report the collection and synthesis of the evidence in a way that is transparent and reproducible. Often, scoping reviews are performed to determine the merit of undertaking the more rigorous, time consuming process of completing a systematic review 2,4.
Systematic reviews
Systematic reviews (SR) are a method of compiling separate studies to answer a research question5. This involves a reproducible methodology for the comprehensive collection and extraction of data from existing studies that meet specific selection criteria for inclusion. They are often, restricted to study designs that produce high-quality, reliable data such as randomized control trials. It is becoming more common for authors of systematic reviews to outline the objectives and methods of the SR in the publication and registration of a protocol that is produced before the SR is undertaken. While the primary purpose of a protocol is to reduce bias through transparency they also allow readers and researchers alike to be aware of SRs underway since they are often a complex and lengthy undertaking.
For further information the Canadian Institute of Health Research (CHIR) provides a robust list of synthesis resources supporting their knowledge translation and commercialization mandate. You may also be interested in the resources consulted while developing this article.
Further resources
Checklist of characteristics (PDF): narrative reviews, scoping reviews, and systematic reviews
Canadian Institute of Health Research: Knowledge Translation and Commercialization. http://www.cihr-irsc.gc.ca/e/29418.html#4.1. Accessed June 9, 2016.
Carter C. Pharmacy: Types of Review Articles. University of Waterloo Library. http://subjectguides.uwaterloo.ca/content.php?pid=243188&sid=5178590. Accessed June 9, 2016.
References
1. Canadian Institute of Health Research: Knowledge Translation and Commercialization. http://www.cihr-irsc.gc.ca/e/29418.html#4.1. Accessed June 9, 2016.
2. Arksey H, O'Malley L. Scoping studies: towards a methodological framework. International journal of social research methodology. 2005;8(1):19-32.
3. Levac D, Colquhoun H, O’Brien KK. Scoping studies: advancing the methodology. Implementation Science. 2010;5(1):1-9.
4. Daudt HM, Van Mossel C, Scott SJ. Enhancing the scoping study methodology: a large, inter-professional team’s experience with Arksey and O’Malley’s framework. BMC medical research methodology. 2013;13(1):1.
5. Higgins J, Green S, eds. Cochrane handbook for systematic reviews of interventions version 5.1. 0. [updated March 2011]. The Cochrane Collaboration; 2011.
