Data extraction and synthesis
Prepare and combine study estimates
Use the alternative synthesis path when pooling is inappropriate. Complete effect-scale, dependence, heterogeneity and uncertainty specifications before filling a result shell. Weighted-mean notation is not an implemented calculation.
Flow diagram
Steps
Extraction specification
Pilot the extraction form, train reviewers and verify extracted data independently.
Link reports to studies
Avoid duplicate participants and estimates across multiple reports.
Harmonize outcomes and estimates
Specify time points, scales, transformations and missing-statistic handling.
Synthesis eligibility
Group compatible comparisons and outcomes; use included studies and study bias assessments.
Is pooling justified?
Document clinical and methodological compatibility; use structured synthesis where pooling is inappropriate.
Main synthesis specification
Specify effect measure, weighting, common-effect or random-effects rationale, uncertainty and dependence.
Analysis and output specification
Prespecify tables and plots; retain planned methods separately from completed estimates.
Synthesis without meta-analysis
If pooling is unsuitable, document the reason, synthesis groups, result-selection rules and structured presentation method. Follow the review-without-meta-analysis guidance for this outcome.
Data extraction and synthesis
End flow
Tables and supporting information
Extraction register
Capture inputs and provenance before combining effects.
Synthesis specifications
Address multi-arm studies, correlated estimates and repeated outcomes.
Planned synthesis table
Result shell: leave all results empty until verified analysis.
Weighted effect notation
For compatible study estimates on a common analysis scale. Define theta_i and model-specific weights w_i; this is notation, not a calculation.
Method evidence
Attach methodological justification and software/version references.