Table 2.
Internal validity according to MMAT
| Study Type | MMAT item | 3 | Can’t tell | No |
|---|---|---|---|---|
| Qualitative (n = 20) | S1. Are there clear research questions? | 20 | ||
| S2. Do the collected data allow to address the research questions? | 20 | |||
| 1.1. Is the qualitative approach appropriate to answer the research question? | 20 | |||
| 1.2. Are the qualitative data collection methods adequate to address the research question? | 18 | 2 | ||
| 1.3. Are the findings adequately derived from the data? | 17 | 3 | ||
| 1.4. Is the interpretation of results sufficiently substantiated by data? | 18 | 2 | ||
| 1.5. Is there coherence between qualitative data sources, collection, analysis and interpretation? | 20 | |||
| Quantitative (n = 6) | S1. Are there clear research questions? | 5 | 1 | |
| S2. Do the collected data allow to address the research questions? | 5 | 1 | ||
| 4.1. Is the sampling strategy relevant to address the research question? | 4 | 2 | ||
| 4.2. Is the sample representative of the target population? | 5 | 1 | ||
| 4.3. Are the measurements appropriate? | 6 | |||
| 4.4. Is the risk of nonresponse bias low? | 2 | 1 | 3 | |
| 4.5. Is the statistical analysis appropriate to answer the research question? | 5 | 1 | ||
| Mixed methods (n = 3) | S1. Are there clear research questions? | 2 | ||
| S2. Do the collected data allow to address the research questions? | 2 | |||
| 5.1. Is there an adequate rationale for using a mixed methods design to address the research question? | 2 | 1 | ||
| 5.2. Are the different components of the study effectively integrated to answer the research question? | 2 | 1 | ||
| 5.3. Are the outputs of the integration of qualitative and quantitative components adequately interpreted? | 2 | 1 | ||
| 5.4. Are divergences and inconsistencies between quantitative and qualitative results adequately addressed? | 1 | 2 | ||
| 5.5. Do the different components of the study adhere to the quality criteria of each tradition of the methods involved? | 1 | 1 | 1 |