Usability of a wearable device for home-based upper limb telerehabilitation in persons with stroke: A mixed-methods study.

Background: The use of wearable technology offers a promising home-based self-directed option for upper limb training. Although product usability is a crucial aspect of users' acceptance of a wearable device, usability studies in wearable devices are rare, with most studies focusing primarily on clinical validity. Objective: This study aimed to explore the usability of a wristwatch device called "Smart reminder" for home-based upper limb telerehabilitation for persons with stroke. Methods: Eleven stroke participants used the proposed wristwatch for at least two weeks and underwent a home-based telerehabilitation program. A mixed-methods design was used to explore the usability of the wristwatch. Quantitative data were collected through the System Usability Scale (SUS) questionnaire, and the participants' rate of therapy compliance (gathered from the device) was reported descriptively. In addition, qualitative data were collected through semi-structured interviews with the participants and were analyzed using thematic analysis. Results: The results demonstrated that the usability of the proposed wristwatch and telerehabilitation system was rated highly by the participants, with a high SUS mean score of 84.3 (12.3) and high therapy compliance rate (mean  =  91%). Qualitatively, all participants reported positive experiences with the wristwatch and indicated keenness to use it again. Participants reported physical improvements and felt motivated to exercise after using the wristwatch. They found the device easy and convenient and appreciated the remote monitoring function. Meanwhile, they highlighted critical considerations for the design of the device and program, including technical support, a wearable design of the device, graded exercise content according to ability, and flexibility in exercise schedules. Finally, they suggested that an interim review with the therapist on their progress might help them continue using the wristwatch. Conclusions: This study's results supported the proposed wearable device's usability and showed strong acceptance by the participants for using it as a home-based upper limb telerehabilitation intervention.