Systematic Reviews & Other Review Types

Scoping reviews are a "preliminary assessment of potential size and scope of available research literature.  Aims to identify nature and extent of research evidence (usually including ongoing research)."  Grant and Booth (2009).

Requires fewer data sources and doesn't require assessing individual studies for risk of bias. 

Often a scoping review is confused with a mapping review.  They are not systematic reviews, but the methodology is closely related. 

Scoping Reviews are best:

• "When a body of literature has not yet been comprehensively reviewed, or exhibits a large, complex, or heterogeneous nature not amenable to a more precise systematic review."

• To map existing literature in terms of nature, features, volume

• To clarify working definitions and conceptual boundaries of a topic or field

• To identify gaps in existing literature/research

(Peters M, Godfrey C, Khalil H, et al)

Timeframe: 12+ months, (same amount of time as a systematic review or longer).

Question: Answers broader questions beyond those related to the effectiveness of treatments or interventions.  A priori review protocol is recommended.

Sources and searches: Is still as comprehensive as a systematic review but much broader.  May involve multiple structured searches rather than a single structured search.  This will produce more results than a systematic review.  Must include a modified PRISMA flow diagram.

Selection: Based on inclusion/exclusion criteria, due to the iterative nature of a scoping review some changes may be necessary.  May require more time spent screening articles due to the larger volume of results from broader questions.

Appraisal: Not applicable for scoping reviews. 

Synthesis: The extraction of data for a scoping review may include a charting table or form.  Results may include a logical diagram or table or any descriptive form that aligns with the scope and objectives of the review.  May incorporate a numerical summary and qualitative thematic analysis.

Source: MDJ Peters et al. (2015), Levac et al. (2010)

• Is not easier than a systematic review.
• Is not faster than a systematic review, may take longer.
• More citations to screen
• Different screening criteria/process than a systematic review
• Often leads to a broader, less defined search.
• Requires multiple structured searches instead of one.
• Increased emphasis for hand searching the literature.
• May require larger teams because of larger volume of literature.
• Inconsistency in the conduct of scoping reviews.

Scoping Study, Systematic Scoping Review, Scoping Report, Scope of the Evidence, Rapid Scoping Review, Structured Literature Review, Scoping Project, Scoping Meta Review

Adapted with permission from Temple University Libraries. https://guides.temple.edu/systematicreviews