Network review overview — Systematic review with network meta-analysis

Question through network comparison

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 and registration where applicable

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.

Search and select

Document reproducible searches and explicit screening decisions. Keep records, reports and studies distinct, with full-text exclusion reasons and study-to-report linkage.

Extract

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.

Define network

Define each treatment node, eligible comparisons and outcome-specific network membership. Inspect connectivity and avoid combining incompatible treatments for convenience.

Assess comparability

Examine whether populations, outcome definitions and effect modifiers support the intended comparisons; document concerns before statistical synthesis.

Synthesize

Apply the prespecified synthesis strategy with documented deviations. Check compatibility, dependence and uncertainty; use structured synthesis when the intended pooling is not defensible.

Assess coherence and certainty

Examine justified alternative assumptions and missing evidence. Assess certainty or confidence for the relevant outcome or comparison, explaining every judgment rather than deriving it from a single test.

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.