JMIR Publications

ABSTRACT

Background:

Good usability is important for the adoption and continued use of mobile health apps (mHealth). In particular, higher usability can support intuitive use by patients, which improves compliance and increases the app's effectiveness. Yet, many usability studies do not use adequate tools to measure perceived usability. The mHealth App Usability Questionnaire (MAUQ) was developed specifically for end users in a medical context. The MAUQ is a relatively new but increasingly used questionnaire to evaluate mHealth apps, but it is not yet available in German.

Objective:

This study aims to translate the MAUQ into German and determine its internal consistency, reliability, and construct validity.

Methods:

This validation study was conducted as part of a usability evaluation project for a mHealth app used as a therapy support tool during breast cancer chemotherapy. The MAUQ questionnaire was translated into German through a rigorous forward-backward translation process, ensuring semantic and conceptual equivalence. Patient responses to the MAUQ and SUS questionnaires were analyzed for validation. Descriptive analysis was performed for the MAUQ subscales and SUS standard scores. Significance tests and correlation coefficients assessed the relationship between SUS and MAUQ results, confirming construct validity. Internal consistency was assessed for item reliability and consistency in measuring the target construct. Free-text questions assessed translation comprehensibility, with responses analyzed descriptively and qualitatively using content analysis.

Results:

In this study, 133 participants responded to the questionnaire, and the validation analysis showed significant positive correlations between the overall MAUQ score and its subscales: Ease of use (r=0.56), Interface and Satisfaction (r=0.75), and Usefulness (r=0.83). These findings support the construct validity of the MAUQ and emphasize the importance of these subscales in assessing the usability of the Enable app. The correlation coefficients ranging from 0.39 to 0.68 for the items further validate the questionnaire by aligning with the overall scoring and capturing the intended concept. The high internal consistency reliability of the MAUQ (α=0.81) and its subscales further enhance the instrument's robustness in accurately evaluating usability in mHealth apps.

Conclusions:

We successfully validated the German translation of the MAUQ standalone version (G-MAUQ) using a standardized approach in a cohort of breast cancer patients. In our validation study, the MAUQ questionnaire exhibited strong internal consistency reliability (α=0.81) across its subscales, indicating reliable and consistent measurement. Furthermore, a significant positive correlation was found between the subscales and the overall score, supporting their consistent measurement of the intended construct. Therefore, the MAUQ questionnaire can be considered a reliable instrument for assessing the usability of mHealth apps in German-speaking adults. The availability of the G-MAUQ will help other researchers in conducting usability studies of mHealth applications in German-speaking cohorts and allow for international comparability of their results.