Literature Searching and Reviews

Scoping reviews are characterized by addressing a slightly broader research question or topic than a traditional systematic review (1), and can thus examine the scope or coverage of literature/evidence on a given topic.
Examples of reasons for conducting a scoping review may include (2):

• To identify different types of available evidence in a given area
• To clarify definitions/concepts in the literature
• To investigate how research is conducted within a given topic or area
• To identify key characteristics or factors related to a concept
• As a predecessor to a systematic review
• To identify and analyze knowledge gaps 

Scoping reviews and systematic reviews have certain commonalities, but also differ from each other on several specific points (2). These similarities and differences are described in the underlying sections (research question and protocol, literature search, literature review). If you need help deciding whether to conduct a systematic review or a scoping review, the article Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach deeper into the similarities and differences between the two. See Types of reviews - How to Select

A Preferred Reporting Item for Systematic reviews and Meta-Analyses (PRISMA) extension exists for scoping reviews (PRISMA-Scr), which is a checklist of 22 essential points that should be included/reported when preparing a scoping review (3).

As initially described, a scoping review is characterized by being based on a broader research question than systematic reviews (1). The research question that forms the basis of the scoping review provides direction and structure to the review. The research question should be clear, as it is the starting point for the development of inclusion and exclusion criteria, literature search, etc. 
Joanna Briggs Institute (JBI) Reviewer´s Manual recommends the conceptualization model PCC (Population, Concept, Context) as a basis for formulating a structured research question for a scoping review. However, there are many other conceptualization models (PICO, PEO etc.) that can contribute to the formulation of a structured research question. See Purpose and Scope.

Unfortunately, scoping review protocols cannot be registered in the international registry PROSPERO, used to register protocols for systematic reviews with health outcomes. Instead, you can create a protocol based on PRISMA for systematic review protocols (PRISMA-P) or JBI Reviewer´s Manual Chapter 10.2: Development of a Scoping Review Protocol and then upload the protocol in a freely accessible place - see Protocol or Search Log. Review Protocol. 

Similar to a systematic review, the literature search is also an essential part of a scoping review and should strive to be as exhaustive as possible. Se Systematic Literature Searching.

Since scoping reviews basically aim to investigate the extent or coverage of literature/evidence on a given topic regardless of its quality, quality assessment of the included studies is typically not performed (although this can be done in relevant cases) (3).

1. Moher D., Stewart L., Shekelle P. All in the Family: systematic reviews, rapid reviews, scoping reviews, realist reviews, and more. Systematic Reviews (2015) 4:183.

2. Munn Z., Peters M.D.J., Stern C., Tufanaru T., McArthur A., Aromataris E. Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach. BMC Medical Research Methodology (2018) 18: 143.

3. Tricco AC, Lillie E, Zarin W, O'Brien KK, Colquhoun H, Levac D, et al. PRISMA Extension for Scoping Reviews (PRISMAScR): Checklist and Explanation. Ann Intern Med. 2018; 169:467–473.

In addition to the literature referenced under References (above), the listed literature below can be recommended for the preparation of scoping reviews:

• Khalil H, Peters M.D.J., McInerney P.A., Godfrey C.M., Alexander L., Evans C., Pieper D., Moraes E.B., Tricco A.C., Munn Z., Pollock D. The role of scoping reviews i reducing research waste. J Clin Epidemiol. 2022; 152: 30 - 35.
• Lockwood C., Tricco AC. Preparing scoping reviews for publication using methodological guides and reporting standards. Nursing & health sciences 2020 22(1):1-4.
• Peters MDJ, Godfrey C, McInerney P, Munn Z, Tricco AC, Khalil, H. Chapter 11: Scoping Reviews (2020 version). In: Aromataris E, Munn Z (Editors). JBI Manual for Evidence Synthesis, JBI, 2020. Link.
• Peters MDJ, Godfrey CM, Khalil H, McInerney P, Parker D, Soares CB. Guidance for conducting systematic scoping reviews. International Journal of Evidence Based Healthcare 2015 Sep;13(3):141-6.
• Pollock, D., Evans, C., Jia, R. M., Alexander, L., Pieper, D., Brandão de Moraes, É., Peters, M. D., Tricco, A. C., Khali, H., Godfrey, C. M., Saran, A., & Munn, Z. (2024). 'How-To:' Scoping Review?. Journal of clinical epidemiology, 111572. Advance online publication. https://doi.org/10.1016/j.jclinepi.2024.111572