Systematic mixed studies reviews are a type of systematic review that combine qualitative, quantitative and mixed methods studies. They are gaining in popularity due to their potential for providing in-depth answers to complex clinical problems and practical concerns. However, several challenges are encountered in systematic mixed studies reviews because of the heterogeneity of included study designs. One of these challenges is related to the quality appraisal of included studies. To address this challenge, a critical appraisal tool for assessing the quality of quantitative, qualitative and mixed methods studies was developed in 2007: the Mixed Methods Appraisal Tool (MMAT). The aim of this project was to strengthen the content validity of the MMAT.

A new version of the MMAT was developed using the results from a literature review on critical appraisal tools and a modified e-Delphi study with methodological experts (n = 73) to identify the core relevant criteria to include in the MMAT.

The results of this project and the new version of the MMAT will be presented. The MMAT has three main characteristics. First, it can be used for different study designs since it includes criteria for qualitative, quantitative and mixed methods studies. Second, the MMAT focuses on the core relevant methodological criteria and has five criteria per category of study. Third, it includes specific criteria for assessing mixed methods studies.

Currently, there exists over 500 critical appraisal tools, making the task of selecting the proper tools for use in systematic mixed studies reviews more difficult. The MMAT offers an alternative solution by proposing a unique tool that can appraise the quality of different study designs. Also, by limiting to core criteria, the MMAT can provide a more time efficient assessment.