Systematic Reviews and Related Evidence Syntheses

Literature (Narrative) Review

A broad term referring to reviews with a wide scope and non-standardized methodology.

• Search strategies, comprehensiveness, and time range covered vary and do not follow an established protocol.

Rapid Review

Applies systematic review methodology within a time-constrained setting.

• Employs methodological “shortcuts” (limiting search terms for example) at the risk of introducing bias.
• Useful for addressing issues needing quick decisions.
• See Evidence summaries: the evolution of a rapid review approach for methodological guidance.

Scoping Review or Systematic Map

Systematically and transparently collects and categorizes existing evidence on a broad topic.

• Seeks to identify research gaps and opportunities for evidence synthesis.
• May critically evaluate existing evidence, but does not attempt to synthesize the results in the way a systematic review would.
• May take longer than a systematic review.
• See Scoping studies: towards a methodological framework.
• See Environmental Evidence Journal Systematic Maps and Guidance on Systematic Maps—CIFOR.

Umbrella Review

Reviews other systematic reviews on a topic.

• Often defines a broader question than is typical of a traditional systematic review.
• Most useful when there are competing interventions to consider.
• See Umbrella Reviews in JBI Manual for Evidence Synthesis

Systematic Review

A methodical and comprehensive literature synthesis focused on a well-formulated research question. 

• Aims to identify and synthesize all of the scholarly research on a particular topic, including both published and unpublished studies.
• Conducted in an unbiased, reproducible way to provide evidence for practice and policy-making.
• May involve a meta-analysis.
• Much more time-intensive than traditional literature reviews.

Meta-Analysis

A statistical technique for combining the findings from disparate quantitative studies.

• Uses statistical methods to objectively evaluate, synthesize, and summarize results.
• May be conducted independently or as part of a systematic review.