Table 2.

Evidence synthesis framework—key features of forms of evidence synthesis outputs

	Evidence synthesis outputs based on a broad thematic overview				Evidence synthesis outputs based on a specific question
Commonly used name	Annotated bibliography	Evidence map	Scoping review	State of the art review	Rapid review	Literature review	Review of reviews	Evidence paper	Mixed methods research synthesis	Systematic review
Also known as		Mapping review	Critical review	Knowledge summary	Evidence summary	Overview	Umbrella review	Evidence briefing	Multi-arm systematic review
		Systematic map	Scoping study		Rapid evidence assessment		Overview of reviews	Briefing note	Mixed studies review
					Interim evidence assessment			Evidence to policy brief
					Brief review			Evidence brief
					Strategy brief			Research summary
Description	A list of key literature and/or sources, primarily of research evidence with expanded summaries on the main content	A map of the existing research evidence base to provide an overview of key themes and/ or results and identify research gaps	An overview of research undertaken on a (constrained) topic, when time and other constraints are limited	A brief review primarily of recent research evidence	A quick review of key, easily accessible evidence, from research and other sources, on a particular (constrained) topic	An overview and synthesis primarily of research evidence with key conclusions	Includes existing reviews, preferably systematic rather than primary studies, and draws a conclusion statement	An extensive overview of available and accessible evidence—both peer reviewed and significant grey literature—primarily from research	A full map and synthesis of different types of research evidence—both quantitative and qualitative—to answer a research question and subquestions	An exhaustive and robust review and synthesis of research evidence
	Often produced for a specific, time bound purpose	Often produced for a specific, time bound purpose	Often produced for a specific, time bound purpose	May include a consensus statement drawing on practice-based evidence	Often produced for a specific, time bound purpose	Is likely to include a critical appraisal of research		Includes a balanced, objective assessment and critical appraisal of the evidence	May include statistical meta-analysis of quantitative medical research and a synthesis of qualitative data	Includes a map of evidence, critical appraisal and qualitative or quantitative evidence synthesis
						May give an indication of areas of consensus and debate		Includes a commentary on evidence	Mixed methods research syntheses include realist reviews and meta-narrative reviews	Includes the criteria (e.g. quality, date range, method) applied to select evidence for synthesis
						Includes peer-reviewed literature and is likely to include grey literature		May consider local context and cost effectiveness		Incorporates peer-reviewed and significant grey literature
										Draws a clear scientific conclusion