The present letter is to thank Drs Shaw, Larkin and Flowers for their enlightening article entitled ‘Expanding the evidence within evidence-based healthcare: thinking about the context, acceptability and feasibility of interventions’,1 and provide complementary information to your readership about synthesis designs and critical appraisal for systematic mixed studies reviews (ie, reviews that include qualitative, quantitative and mixed methods studies).

We recently published an overview of mixed methods, which describes four main types of rigorous synthesis designs for systematic mixed studies reviews (and related techniques): convergence qualitative (thematic synthesis, metanarrative synthesis, …