Harnessing Energies, Resolving Tensions: Acknowledging a Dual Heritage for Qualitative Evidence Synthesis.

Qualitative evidence synthesis (QES) encompasses more than 20 methods for synthesizing qualitative accounts of research phenomena documenting real-life contexts. However, tensions frequently arise from the different heritages that shape QES methodology: namely, systematic reviews of effectiveness and primary qualitative research. Methodological innovations either derive from each heritage or are stimulated when both are in juxtaposition; it is important to broker a rapprochement. This article draws on practical experience from a range of syntheses and methodological development work conducted with the Cochrane Qualitative and Implementation Methods Group. The legacy of both heritages is briefly characterized. Three stages of the QES process offer exemplars: searching/sampling, quality assessment, and data synthesis. Rather than an antagonistic clash of research paradigms, this dual heritage offers an opportunity to harness the collective energies of both paradigms. Future methodological research is needed to identify further applications by which this dual heritage might be optimally harnessed.