20.3.1  Exemplar of synthesizing qualitative evidence to supplement a Cochrane Intervention review: directly observed therapy and tuberculosis (TB)

Before considering methodology for qualitative evidence synthesis, we provide an exemplar, summarized in Box 20.3.a. The full review is published in the Journal of Advanced Nursing (Noyes 2007). This parallel qualitative evidence synthesis both extends and supplements a Cochrane Intervention review of directly observed therapy (supervised swallowing of medication) as an intervention to improve peoples’ adherence to TB regimens (Volmink 2007), which included six randomized trials but found no statistically significant effect of directly observed therapy (DOT) when compared with people treating themselves at home. The accompanying synthesis of qualitative evidence focuses on lay experiences and perceptions of TB treatment to consider whether evidence from these studies could help explain the results of the randomized trials and contribute to the development of policy for the treatment of TB. In doing so the qualitative evidence synthesis addressed questions beyond those of the Cochrane Intervention review such as the appropriateness of DOT and the way it was facilitated in practice.