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

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.

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.

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.

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.

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.