Five common pitfalls in mixed methods systematic reviews: lessons learned

Mixed methods systematic reviews (MMSRs) combine quantitative and qualitative evidence within a single review. Since the revision of the JBI methodology for MMSRs in 2020, there has been an increasing number of reviews published that claim to follow this approach. A preliminary examination of these indicated that authors frequently deviated from the methodology. This article outlines five common 'pitfalls' associated with undertaking MMSR and provides direction for future reviewers attempting MMSR.

Forward citation tracking identified 17 reviews published since the revision of the JBI mixed methods methodological guidance. Methods used in these reviews were then examined against the JBI methodology to identify deviations.

The issues identified related to the rationale for choosing the methodological approach, an incorrect synthesis and integration approach chosen to answer the review question/s posed, the exclusion of primary mixed methods studies in the review, the lack of detail regarding the process of data transformation, and a lack of 'mixing' of the quantitative and qualitative components.

This exercise was undertaken to assist systematic reviewers considering conducting an MMSR and MMSR users to identify potential areas where authors tend to deviate from the methodological approach. Based on these findings a series of recommendations are provided.