Usability testing of the Set Brave Goals app, a continence goal-selection app for children with spina bifida.

Introduction: The Set Brave Goals app is the first digital health app (DHA) aimed at helping children with spina bifida (SB) aged 8-17 years old to select and track their urinary and fecal continence goals. Developed by children, parents, providers and researchers, its usability, or appropriateness to a purpose ("user-friendliness"), remains unknown. In an alpha testing stage, our aim was to determine the usability of the app prior to clinical use.

Methods: We recruited children with SB and their parents in clinic and via social media. A recruitment goal of 10 children exceeded industry standard of 5 participants (10 participants are expected to identify approximately 96% of usability problems). Participants downloaded and used the app for a week. They completed a questionnaire, including the System Usability Scale (SUS) and closed and open-ended questions. The SUS is a 10-item validated usability questionnaire most widely used in DHA usability testing (scores range from 0 to 100, 100 representing greatest usability). Median/mean SUS scores for DHAs are 68. Mann-Whitney-U and t-tests were used.

Results: Ten children with SB participated (median age: 14 years old, 6 female, 8 shunted, 8 using bladder catheterizations). Twenty parents participated (17 mothers, median age: 42 years old). Median SUS score was 77.5 for children and 73.8 for parents, corresponding to "good" to "excellent" usability (Summary Figure). There were no significant differences between child/parent scores (p = 0.69) or those for other DHAs (p = 0.11). It took a median 5-10 min to go through the app (2 parents felt it took too much time). All participants felt the app was easy to understand and use (100%). Most participants would recommend it to children and parents (children: 89%, parents: 80%), and believed it would be valuable to children (90%, 75%) and urologists (80%, 80%). Free text responses related to more varied color schemes, keeping free-text notes within the app and more flexible goal/alarm setting. These changes were incorporated into the app.

Comment: Usability testing prior to clinical launch identified areas for app improvement. Although this study sample met industry standards, findings are limited by a small group of participants. The app will undergo further refinement during prospective beta testing.

Conclusions: The Set Brave Goals app for children with SB has acceptable usability parameters. This justifies proceeding with wider use to formalize children's continence goal setting/tracking and testing its value to children with SB and their healthcare providers.