Usability testing of a smartphone application designed for individuals with prediabetes: Involving end-users in development (Preprint)

BACKGROUND Background: Technology is more likely to be used when it is designed to meet the needs of end-users. To supplement the [PROGRAM] diabetes prevention program, a smartphone application was developed in partnership with past [PROGRAM] clientele. OBJECTIVE A focus group with seven participants was conducted to examine the application’s usability and collect feedback for future iterations. METHODS Past [PROGRAM] clientele participated in a cognitive walkthrough (CW) of eight novel tasks and completed the System Usability Scale (SUS) survey. Participants were then given the option to use the application for three weeks before completing the user Mobile Application Rating Scale (uMARS). RESULTS Analysis of the CW identified 26 usability problems; each were coded using a heuristic evaluation to describe usability errors. The most frequently coded errors included inappropriate progress feedback, information appearing in an illogical order, counterintuitive design, and issues with application aesthetics. A mean summary score of 66.8% was reported for the SUS, representing a marginal acceptability score and indicating that design issues needed to be resolved. A uMARS mean score of 3.59±0.33 was reported, implying an average acceptability rating. CONCLUSIONS These findings identified necessary improvements in the application, ranging from minor aesthetic problems to major functionality problems. Involving end-users allows the application to be tailored to the client’s preferences and increases the likelihood of usage. This application aligns with [PROGRAM]’s program components and behavior change techniques which can improve health outcomes for future clients and allow them to self-monitor their exercise, diet, and goals.