Table 4.

Evidence synthesis framework—technical characteristics of different 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
Quality appraisal of evidence	Limited	Limited	Limited	Limited	Limited	Limited	Essential	Essential	Essential	Essential
Evidence usually presented as	Reference list	Graphics and tables	Narrative and tables	Narrative, graphics and tables	Narrative and tables	Narrative	Narrative, graphics and tables	Narrative and tables	Narrative, graphics and tables	Narrative and tables
Systematic documentation of evidence	Limited	Comprehensive	Limited	Limited	Comprehensive	Comprehensive	Comprehensive	Comprehensive	Comprehensive	Comprehensive
Replicable	Low	Medium	Low	Low	Medium	Medium	Medium	Low	Medium	High
Periodic update	Possible	Possible	Possible	Possible	Possible	Possible	Essential	Possible	Possible	Essential
Limitations	Does not synthesize or analyse findings across sources	Overview, not in-depth analysis	May have: A narrow focus question	-Evidence base not comprehensive, limited to most recent scientific information	Evidence base not comprehensive	Prone to selection and publication bias - tends to review readily available evidence	Does not include research outside existing reviews	Limited accessibility to literature	Time consuming and resource intensive	Resource intensive (time, human, financial)
	Generally does not appraise evidence	Does not synthesize or analyse findings across sources	Few search sources	May be prone to bias	Relies on easily accessible/ available evidence	Often limited detail on search strategies, or how conclusions reached	Because reviews are of variable quality, each needs to be assessed for how systematic and comprehensive it is	Time/human resource constraints likely to limit scope		May have a narrow clinical question or set of questions
	Prone to selection and publication bias	A range of evidence may be covered, but generally relies on few search sources	Use only key terms for search (not all variants)		Prone to selection and publication bias	Resources determine scope, which may limit comprehensive-ness or lead to inconclusive findings		Limited literature search		Has a history of use in health and education; yet to be fully tested in other development areas, e.g. governance and climate change
		Prone to selection and publication bias	Be limited to electronic and easily available documents		Risk of generating inconclusive findings that provide a weak answer to the original question
	;		A simple description with limited analysis