Usability of mHealth-delivered physical activity after mild stroke or transient ischemic attack: the role of therapist engagement and user barriers

Background Mobile Health (mHealth) is a promising tool for supporting long-term physical activity following stroke or transient ischaemic attack (TIA), but its usability in this population remains unclear. This study aimed to: (1) compare the perceived usability of mHealth-delivered physical activity support among individuals post-stroke or TIA who received frequent physiotherapist support versus those who received infrequent support; and (2) identify factors associated with positive perceptions of mHealth usability. Methods Adults with stroke or TIA were randomised to either a 6-month mHealth version of the i-REBOUND programme (frequent physiotherapist mHealth support) or a control group (infrequent physiotherapist mHealth support). Usability was assessed at 3 and 6 months using a modified Telehealth Usability Questionnaire. Group comparisons were conducted using chi-square tests, and multiple logistic regression was used to identify factors associated with positive usability perceptions following intervention completion. Results Of the 114 participants, 51 (89%) in the i-REBOUND programme and 53 (93%) in the control group adhered to ≥ 40% of the intervention. At 3 months, more participants in the i-REBOUND group than in the control group reported easy access to the physiotherapist via chat (90% vs. 64%; P = .002) and a willingness to use mHealth again (90% vs. 66%; P = .003). At both follow-ups, a higher proportion of i-REBOUND participants reported improved access to physiotherapy (65–71% vs. 36–40%; P ≤ .004) and found mHealth acceptable (78–80% vs. 53–55%; P ≤ .002). Usability domains related to reliability—such as managing technical issues and clarity of error messages—were rated low in both groups. Visual difficulties using a smartphone (odds ratio = 0.34, P = .047) and high stress levels (score ≥ 15 on the DASS-21 stress scale; odds ratio = 0.19, P = .050) were independently associated with lower usability perceptions. Conclusion mHealth-delivered support for physical activity was perceived as acceptable and accessible by people post-stroke or TIA, with higher usability reported in the group receiving regular physiotherapist support. Visual impairments and elevated stress levels were associated with lower perceptions of usability, which is an important finding for the future development of mHealth interventions post-stroke or TIA. Trial Registration ClinicalTrials.gov Identifier NCT05111951. Registered November 8, 2021.