Systematic Reviews
Comprehensive, protocol-led review of a defined question
Evidence Synthesis
Turning published and available evidence into rigorous, transparent and decision-relevant synthesis.
Structured support from an answerable question to useful synthesis
The review approach is selected according to the question, evidence base, study designs, timeframe and intended use.
Evidence can be extensive, inconsistent or difficult to translate into a clear conclusion. Support can clarify the review question, identify studies systematically, assess their credibility and synthesise what is known, uncertain and missing.
Engagements may cover a complete protocol-led review or defined stages such as literature searching, screening and study selection, data extraction, critical appraisal, quantitative synthesis or transparent reporting.
A review design suited to the purpose
These approaches answer different kinds of questions and are not interchangeable.
Meta-Analysis
Statistical pooling where studies and assumptions are sufficiently comparable
Scoping Reviews
Mapping the breadth, concepts and gaps in a field
Rapid Evidence Reviews
Time-sensitive synthesis using explicit, proportionate methods
Evidence Mapping
Structured overview of evidence distribution and gaps
Structured / Narrative Synthesis
Transparent thematic or structured synthesis where pooling is unsuitable
A transparent path through the evidence
Decisions and exclusions are documented so the relationship between the question, included evidence and conclusions remains clear.
Question
Protocol
Search
Screening
Extraction
Critical appraisal
Synthesis
Interpretation & reporting
Pool results only when comparison and assumptions are defensible
Meta-analysis is not inherently superior to a structured narrative synthesis, and a pooled estimate is not always appropriate.
Quantitative pooling may be useful when study designs, populations, interventions or exposures, outcomes and measures are sufficiently comparable. Effect estimates should be interpreted with heterogeneity, study quality or risk of bias, uncertainty and the review context in view.
Subgroup or sensitivity analysis can examine robustness where supported, but cannot remove limitations in the underlying evidence. When pooling could obscure important differences or mislead, structured narrative synthesis or evidence mapping provides the more defensible account.
Synthesis for research and decision needs
- Policy and programme questions
- Public health and clinical research
- Development and humanitarian evidence
- Research-priority and evidence-gap assessment
Useful and auditable review products
- Systematic review protocols
- Search strategies
- Screening frameworks
- Evidence extraction frameworks
- Evidence tables
- Risk-of-bias / quality assessments
- Evidence maps
- Narrative syntheses
- Meta-analyses where appropriate
- Evidence summaries
Connect synthesis with wider evidence work
Explore scholarly outputs, research areas or complementary analytical support without duplicating the research record here.
Have a research question that requires a rigorous evidence synthesis?
Share the review question, evidence need and reporting requirement to discuss an appropriate approach.