Synthesis when meta-analysis is not possible: approaches to grouping, presentation and synthesis

Workshop category: 

  • Other topics
Date and Location


Wednesday 23 October 2019 - 16:00 to 17:30


Contact persons and facilitators

Contact person:


McKenzie J1, Brennan S2
1 Monash University, Australia
2 Cochrane Australia, Monash University, Australia


Thomson H1, Ryan R2, Johnston R3
1 Cochrane Public Health Review Group, University of Glasgow, Scotland
2 Cochrane Consumers and Communication Review Group, La Trobe University, Australia
3 Cochrane Musculoskeletal Review Group, Monash University, Australia
Target audience

Target audience: 

Review authors

Level of difficulty: 

Type of workshop

Type of workshop : 



Background: in reviews where meta-analysis is not used, authors commonly report results study-by-study or draw conclusions without reporting how they interpreted findings across studies. These approaches may leave decision makers to make sense of findings themselves, and undermine confidence in the evidence. There are many circumstances that may preclude the use of meta-analysis of effect estimates. For example, when there is incomplete information reported about the intervention effect estimates (e.g. missing standard errors), or inconsistency in the reported effect metrics across studies. Other commonly cited reasons for not using meta-analysis can often be addressed through grouping, such as when there is sparse data arising from studies reporting diverse interventions or outcome measures. This workshop will provide potential solutions for these circumstances and is based on new guidance in version 6 of the Cochrane Handbook for Systematic Reviews of Interventions (Chapters 3 and 12).

Objectives: in this workshop we will
1) consider options for grouping studies to facilitate synthesis, and
2) provide guidance on presentation and synthesis methods that can be used when meta-analysis of effect estimates is not possible (sometimes referred to as 'narrative synthesis').

Description: in this workshop we will use a mix of practical exercises, interactive examples, and presentation to:
1) discuss scenarios that may preclude meta-analysis;
2) explore options for structuring reviews to facilitate syntheses (by grouping interventions and outcomes using taxonomies and frameworks);
3) present other synthesis and presentation methods, along with their advantages and disadvantages and guidance on when to use which approach; and
4) provide suggestions for describing the results of the synthesis.

Participants will work through an example examining approaches to synthesise data on patient satisfaction with care. Planning for circumstances that may preclude meta-analysis can ensure that review authors make the best use of available data and produce more useful syntheses for decision makers.