Table 3

Mixed-methods studies. Quality assessed using the Mixed Methods Appraisal Tool (MMAT)

Criteria for mixed-methods characteristics of mixed-methods studies
Authors	S1. Are there clear research questions?	S2. Do the collected data allow to address the research questions?	5.1. Is there an adequate rationale for using a mixed-methods design to address the research question?	5.2. Are the different components of the study effectively integrated to answer the research question?	5.3. Are the outputs of the integration of qualitative and quantitative components adequately interpreted?	5.4. Are divergences and inconsistencies between quantitative and qualitative results adequately addressed?	5.5. Do the different components of the study adhere to the quality criteria of each tradition of the methods involved?
Kim et al 57	Yes	Yes	No	Yes	Yes	Yes	Partial
Nolan et al 58	Yes	Yes	Partial	Yes	Yes	Yes	Partial
Puts et al 59	Yes	Yes	Yes	Partial	Partial	Yes	Partial
Criteria for qualitative component of mixed-methods studies
	1.1. Is the qualitative approach appropriate to answer the research question?	1.2. Are the qualitative data collection methods adequate to address the research question?	1.3. Are the findings adequately derived from the data?	1.4. Is the interpretation of results sufficiently substantiated by data?	1.5. Is there coherence between qualitative data sources, collection, analysis and interpretation?
Kim et al 57	Partial	Yes	Yes	Yes	No
Nolan et al 58	Partial	Yes	Yes	Yes	Yes
Puts et al 59	Yes	Yes	Yes	Yes	Yes
Criteria for quantitative component of mixed-methods studies
	4.1. Is the sampling strategy relevant to address the research question?	4.2. Is the sample representative of the target population?	4.3. Are the measurements appropriate?	4.4. Is the risk of non-response bias low?	4.5. Is the statistical analysis appropriate to answer the research question?
Kim et al 57	Yes	Partial	Yes	No	Yes
Nolan et al 58	Yes	Partial	Yes	Partial	Yes
Puts et al 59	Yes	Partial	Can't tell	No	Partial

Rating mixed-methods studies using MMAT involves scoring criteria 1.1–1.5 (qualitative dimension) plus (criteria 2.1–2.5 (quantitative—RCTs) or criteria 3.1–3.5 (quantitative—non-randomised trials) or criteria 4.1–4.5 (quantitative descriptive)) plus criteria 5.1–5.5 (mixed methods).
Criteria 2.1–2.5 or criteria 3.1–3.5 of the MMAT are not listed here because none of these studies are intervention studies.
RCT, randomised controlled trial.