Usability and feasibility assessment of the Huntington Support App (HD-eHelp study): a mixed-methods multi-study report

eHealth holds great promise for managing rare and complex neurodegenerative diseases, such as Huntington’s disease (HD). To address this potential, the Huntington Support App (HSA) was developed to provide reliable information on HD, news updates, and contact possibilities tailored primarily to the needs of HD gene expansion carriers (HDGECs) and their partners. Building on prior research outlining the HSA’s co-creation process with HDGECs, partners and health care providers (HCPs), the present study offers an in-depth mixed-methods evaluation of the HSA in practice in the Netherlands. This research comprises a multi-study report assessing the usability of the HSA through a think-aloud method (Study 1) and subsequent feasibility testing in a real-world setting (Study 2). In the first study, 4 HDGECs, 4 partners, and 4 HCPs, who themselves were not involved in the HSA co-design, provided real-time feedback on usability while using the HSA final prototype. In the feasibility study, a first version of the HSA was publicly launched and made available to the larger HD community for feedback (including HDGECs, partners, HCPs and family/friends, n = 13). In both studies, the System Usability Scale (SUS) was administered, and quantitative data were triangulated with qualitative findings. Overall, participants were positive about the app’s usability in both studies. Participants’ SUS scores in the first study (76.6) were notably higher than those in the second study (68.8), with the scores in the first study far exceeding the benchmark usually seen in usability testing for healthcare apps. Furthermore, in both studies there were variations in ratings among participant groups, with HDGECs, partners and family/friends viewing the app more favorably than HCPs, who generally expressed a more neutral opinion. Qualitative responses further complemented these findings and highlighted suggestions for the app’s improvement, particularly in terms of content and navigation. The HSA was well-received by members of the HD community, indicating alignment with their needs. Future efforts should address identified areas for improvement of the app. Our findings underscore the importance and feasibility of a participatory, human-centered design approach for complex and rare diseases like HD and highlight its relevance for future co-design initiatives of eHealth services for other rare neurodegenerative diseases.