Cochrane Qualitative and Implementation Methods Group Guidance paper 2: Methods for assessing methodological limitations, data extraction and synthesis, and confidence in synthesized qualitative findings

The Cochrane Qualitative and Implementation Methods Group develop and publish guidance on the synthesis of qualitative and mixed-method implementation evidence. Choice of appropriate methodologies, methods and tools is essential when developing a rigorous protocol and conducting the synthesis. Cochrane authors who conduct qualitative evidence syntheses have thus far used a small number of relatively simple methods to address similarly written questions. Cochrane has invested in methodological work to develop new tools and to encourage the production of exemplar reviews to show the value of more innovative methods that address a wider range of questions. In this paper in the series we report updated guidance on the selection of tools to assess methodological limitations in qualitative studies, and methods to extract and synthesise qualitative evidence. We recommend application of GRADE-CERQual to assess confidence in qualitative synthesised findings. This guidance aims to support review authors to undertake a qualitative evidence synthesis that is intended to be integrated subsequently with the findings of one or more Cochrane reviews of the effects of similar interventions. The review of intervention effects may be undertaken concurrently with or separate to the qualitative evidence synthesis. We encourage further development through reflection and formal testing.