Review overview — Systematic review without meta-analysis
Question through structured synthesis
Flow diagram
Steps
Question
Define the review question, intended decision and eligibility framework. Use PICO for intervention comparisons, PCC for scoping, or test/condition/clinical-role definitions for accuracy reviews.
Protocol
Write the planned eligibility, search, selection, extraction, appraisal and synthesis methods before conducting the review. Record registration where eligible, or a public protocol location, and date subsequent amendments.
Registration where applicable
Check the registry’s current eligibility and register prospectively where applicable. Record the identifier and timing; if ineligible, document a public protocol location and rationale.
Search
Choose information sources and supplementary search routes, retain reproducible strategies and dates, and plan an update search before final interpretation.
Select
Pilot eligibility criteria, record reviewer decisions and resolve disagreements. Link multiple reports to their underlying study or evidence source.
Extract and appraise
Pilot fields, definitions and source-location capture. Verify important entries and retain study/report linkage. Use linked detailed flows for extraction and any associated appraisal.
Group evidence
Prespecify synthesis groups by relevant design, population, intervention, outcome and time point. Record how multiple eligible results from one study will be selected.
Synthesize
Apply the prespecified synthesis strategy with documented deviations. Check compatibility, dependence and uncertainty; use structured synthesis when the intended pooling is not defensible.
Interpret and report
Report methods, deviations, selection, findings and limitations using the relevant reporting guidance. Separate planned table shells from verified results and archive reproducible materials where permitted.
Review overview
End flow
Tables and supporting information
Protocol and decision register
Record the protocol, approvals and registration where applicable. Preserve planned decisions and amendments separately from results.
Protocol and rationale evidence
Attach the research rationale, protocol, registration and supporting evidence. Leave unverified citations empty.