Scoping reviews are similar to systematic reviews but differ significantly in their purpose and method, making it important to examine these distinctions. They systematically analyze existing literature without the limits of quality assessment, revealing overarching patterns, research gaps, and valuable insights in various research landscapes.
This article is the fourth installment in the ongoing series, Understanding Literature Reviews in Healthcare. In previous posts, weโve examined Narrative Reviews, Systematic Reviews, and Meta-analyses.
Scoping Reviews
In healthcare research, scoping reviews explore the breadth and depth of available studies on a particular topic. Rather than focusing on a narrowly defined question (as in systematic reviews), scoping reviews take a broader view. Theyโre designed to:
- Map key concepts
- Identify the types of evidence available
- Uncover research gaps
While they follow a systematic process, scoping reviews do not typically assess the quality of included studies.1,2 Think of a scoping review as a structured but expansive literature overview, almost like a โsystematic narrative review.โ
Pros and Cons
Pros of Scoping Reviews
- Broad Overview of Literature: These reviews offer a comprehensive mapping of existing studies, making it easier to visualize the entire research landscape
- Concept Clarification: Assist researchers in grasping complex, emerging, or overlapping concepts within a field
- Gap Identification: Useful for spotting missing or underexplored areas in existing research
- Informs Future Research: Often serves as a precursor to systematic reviews, helping refine inclusion criteria or generate targeted research questions1,3
Cons of Scoping Reviews
- No Quality Assessment: Because they donโt appraise study rigor, the findings may not always be suitable for guiding practice or policy
- Time and Resource Intensive: While more flexible than systematic reviews, scoping reviews still demand more time and effort than a narrative review
- Risk of Superficial Analysis: With a broader scope, some critical topics may receive less in-depth attention
- Methodological Inconsistencies: The lack of universal standards for scoping reviews can lead to variable methods and reporting styles4
Methodology/Guidelines
Scoping reviews historically had fewer formal resources than systematic reviews, but that landscape is rapidly changing. The JBI (formerly Joanna Briggs Institute) has developed excellent methodological guidelines that researchers can rely on for structure and consistency.
Methodology
- Chapter 10: Scoping Reviews from the JBI Manual for Evidence Synthesis: Provides detailed instructions and interim updates for evolving methods
- Arskey & OโMalley Framework: A foundational five-stage approach widely adopted for designing and conducting scoping reviews
- Levac, Colquhoun, & OโBrien: Expands on the Arskey & OโMalley Framework
Protocols
While registering a protocol for a scoping review isnโt always mandatory, itโs increasingly seen as best practice for transparency and reproducibility.5
- Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P): A modified version of the original PRISMA checklist tailored for protocols
- Best Practice Guidance and Reporting Items for the Development of Scoping Review Protocols: Peters et al. provide practical guidance on structuring protocols for scoping reviews using the PRISMA-P checklist.
Reporting Guidelines
Even though scoping reviews differ from systematic reviews in purpose and scope, they still require a structured and transparent reporting process.
- PRISMA for Scoping Reviews (PRISMA-ScR): An extension of the PRISMA checklist that ensures comprehensive and standardized reporting for scoping reviews
- PRISMA Extension for Scoping Reviews (PRISMA-ScR): Checklist and Explanation: ย Explains the development of the checklist and shares some helpful tips on how to make the most out of it
Examples
To better understand how scoping reviews are used in practice, here are two well-cited studies that examine scoping reviews themselves:
- Pham MT, Rajiฤ A, Greig JD, Sargeant JM, Papadopoulos A, McEwen SA. A scoping review of scoping reviews: advancing the approach and enhancing the consistency. Res Synth Methods. 2014 Dec;5(4):371-85. doi: 10.1002/jrsm.1123. Epub 2014 Jul 24. PMID: 26052958; PMCID: PMC4491356.
- Tricco AC, Lillie E, Zarin W, OโBrien K, Colquhoun H, Kastner M, Levac D, Ng C, Sharpe JP, Wilson K, Kenny M, Warren R, Wilson C, Stelfox HT, Straus SE. A scoping review on the conduct and reporting of scoping reviews. BMC Med Res Methodol. 2016 Feb 9;16:15. doi: 10.1186/s12874-016-0116-4. PMID: 26857112; PMCID: PMC4746911.
Learn More
Want to take your understanding of scoping reviews to the next level? Take a look at these resources!
- JBI Scoping Review Network Resources: The JBI Scoping Review Methodology Group has created excellent resources, including a template (download the template as a Word document)
- Scoping Reviews guide by University of North Carolina at Chapel Hill Health Sciences Library: Offers a practical guide with methodological steps, valuable tools, and real examples
- Guidance for Conducting Systematic Scoping Reviews: Peters et al. offer a detailed guide on how to plan and carry out scoping reviews, highlighting the importance of rigor, clarity, and transparency
Final Thoughts on Scoping Reviews
Scoping reviews play a crucial role in healthcare research by providing a structured yet adaptable approach to exploring broad topics and mapping the existing literature. Although they may not offer definitive answers like systematic reviews, their ability to clarify concepts, identify knowledge gaps, and inform future investigations makes them invaluable for researchers at all stages. Whether you are just starting to explore a topic or establishing the foundation for a more detailed review, a well-conducted scoping review can illuminate the way forward.
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References
- Munn Z, Pollock D, Khalil H, Alexander L, Mclnerney P, Godfrey CM, et al. What are scoping reviews? Providing a formal definition of scoping reviews as a type of evidence synthesis. JBI Evid Synth [Internet]. 2022;20(4). Available from: https://journals.lww.com/jbisrir/fulltext/2022/04000/what_are_scoping_reviews__providing_a_formal.2.aspx
- Peters MDJ, Marnie C, Tricco AC, Pollock D, Munn Z, Alexander L, et al. Updated methodological guidance for the conduct of scoping reviews. JBI Evid Synth. 2020 Oct;18(10):2119โ26.
- Munn Z, Peters MDJ, Stern C, Tufanaru C, McArthur A, Aromataris E. Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach. BMC Med Res Methodol. 2018 Nov 19;18(1):143.
- Khalil H, Peters MDJ, Tricco AC, Pollock D, Alexander L, McInerney P, et al. Conducting high quality scoping reviews-challenges and solutions. J Clin Epidemiol. 2021 Feb 1;130:156โ60.
- Peters MDJ, Godfrey C, McInerney P, Khalil H, Larsen P, Marnie C, et al. Best practice guidance and reporting items for the development of scoping review protocols. JBI Evid Synth [Internet]. 2022;20(4). Available from: https://journals.lww.com/jbisrir/fulltext/2022/04000/best_practice_guidance_and_reporting_items_for_the.3.aspxย
