Literature Reviews & Evidence Syntheses

There are a number of types of evidence syntheses. Below, each of the most common types are defined, and an example from a published paper is included. Note that the example articles are available through Lavery Library subscriptions and may require you to sign into your Fisher account.

• A broad term referring to reviews with a wide scope and non-standardized methodology
• Search strategies, search comprehensiveness, and time range for selected sources will vary and do not follow an established protocol.
• Very common for use in undergraduate and graduate student assignments

Example from published literature

• Systematic and transparent method used to collect and categorize existing evidence on a broad question of scientific, policy, or management importance
• Compares, evaluates, and synthesizes evidence to look for an effect of an intervention
• Takes time, in some cases up to a year or more, to complete
• Most commonly referred to as type of evidence synthesis; sometimes confused as a blanket term for other types of reviews

Example from published literature

• Systematic and transparent method used to collect and categorize existing evidence on a broad question of scientific, policy, or management importance
• Looking to identify research gaps and opportunities for evidence synthesis rather than searching for the effect of an intervention
• May critically evaluate evidence, but does not attempt to synthesize the results in the same way as systematic reviews (see reporting/writing guidelines from Environmental Evidence Journal's Systematic Map and Evidence-Based Forestry's Guidance on Systematic Maps)
• Takes time to complete, potentially longer than a systematic review
• To learn more about scoping reviews read Arksey & O'Malley's 2007 paper: Scoping Studies: Towards a methodological framework

Example from published literature

• Systematic and transparent method used to collect and categorize existing evidence on a broad question of scientific, policy, or management importance
• Answers questions about practice by evaluating the quality of each study included in the review and interprets and synthesizes studies into meaningful conclusions
• Differs from a systematic review in that they look "more broadly at a phenomenon of interest . . .and allows for diverse research, which may contain theoretical and methodological literature" (Toronto & Remington, 2020, p. 2)

Example from published literature

Toronto, C. E., & Remington, R. (Eds.). (2020). A step-by-step guide to conducting an integrative review. Springer International Publishing AG.

• Studies for a Meta-analysis should be selected using systematic review searching methods
• Statistical technique for combining the findings from quantitative studies
• Results are portrayed with a Forest Plot to show strength and direction of effect

Example from published literature

• Studies for a Meta-synthesis should be selected using systematic review searching methods
• An approach to analyze data across qualitative studies
• Uses established methodologies to triangulate, code and translate study data. See Guidance on choosing qualitative evidence synthesis methods for use in health technology assessments of complex interventions p.16 for more information on Qualitative Synthesis Methods

Example from published literature