Subgroup analyses

This page details the steps to create analyses using study centric data. All new protocols created from 25 April 2023 have study centric data management enabled. 

See Should I use study centric data management in my review?

Subgroup analyses may be done as a means of investigating heterogeneous results, or to answer specific questions about particular patient groups, types of intervention or types of study (as well as clinical heterogeneity there is methodological heterogeneity). More information is available in Section 10.11 of the Cochrane Handbook for Systematic Reviews of Interventions.  

When setting up the review criteria (see step 1 for study centric data), you can define covariates and associated categories. Covariates are study characteristics that might influence the size of the intervention effect. If you would like to investigate certain study characteristics with subgroup analyses or to filter with for sensitivity analyses, you must specify this in your protocol.  

Before you begin, you need to have set up your review criteria, entered your results, and created your analyses (steps 1 to 3 of using data centric data). 

On the main Analyses page, create or select the Analysis you want to add a subgroup to. On the Option tab, within the Synthesis PICO, you can specify the subgroup factor for the analyses (i.e. the covariate). It is also useful to indicate this is a subgroup analysis in the Analysis Name. 

The example is subgrouping by the Covariate Dropouts. 

When you click on the 'Graphs' tab, you will get the forest plot with the subgroup analysis by the predefined category. In this example, whether dropouts were >4%, 4% or <4% in the included studies.