Usability testing of a mobile health application to support individuals with active tuberculosis: a mixed methods study

Poor adherence to tuberculosis (TB) treatment leads to further disease transmission, worsened outcomes, and the development of drug resistance. Digital adherence technologies may facilitate a more patient-centered approach for improving TB treatment outcomes than current strategies. The objective of this study was to evaluate and explore improving usability of the TB Treatment Support Tools (TB-TST) mobile application. We used an iterative convergent mixed-method design consisting of two quantitative surveys and a qualitative think-aloud interview. Testing was conducted in three testing cycles consisting of a total of 16 interviews and 26 surveys. Results were thematically analyzed and reported to the development team during weekly team meetings. Participants rated the TB-TSTs application as having high usability and the iterative approach resulted in several refinements to the application in response to participant feedback. These refinements were well received during qualitative interviews but did not result in a statistically significant improvement in usability testing scores between cycles. Using an iterative convergent mixed-method design was an effective method for refining our mHealth application. Data collected from think-aloud interviews, the MAUQ, and the Health-ITUES identified key areas of application design that needed refinement.