App-based exercise intervention versus supervised exercise therapy for patients with hip or knee osteoarthritis-the randomised noninferiority DigiOA trial.

Objectives: Incorporating technology in the treatment of osteoarthritis is seen as a viable solution to preserve the sustainability of the healthcare system. We aimed to determine whether the use of an exercise app was noninferior to supervised exercise therapy in patients with hip/knee osteoarthritis. Methods: In this noninferiority randomised controlled trial, patients with hip/knee osteoarthritis in primary care physiotherapy in Norway were provided individually tailored exercise therapy for 6 weeks randomly assigned 1:1 to either in-person delivery (standard treatment) or delivery through an app (experimental treatment). Both groups received patient osteoarthritis education prior to randomisation. The primary outcome was the proportion of OMERACT-OARSI (Outcome Measures in Rheumatology-Osteoarthritis Research Society International) responders (change in pain, physical function, and disease activity) at 6 weeks postrandomisation. Results: Between July 2021 and December 2023, 103 patients were assessed for eligibility; 68 patients (43% of the calculated sample size) participated in patient education and were randomly allocated to the standard or the experimental group, resulting in 34 patients in each group. At 6 weeks, 53 (78%) reported on the primary outcome. Fifteen patients fulfilled the OMERACT-OARSI responder criteria, of which 7 were in the standard and 8 in the experimental treatment group, respectively. Risk difference between the groups was 0.03 (95% CI -0.22, 0.27). Conclusions: The results indicate a potential positive effect of app-based exercise at 6 weeks follow-up; however, we cannot conclude whether app-based exercise was noninferior to in-person supervised exercise therapy as the lower bound of the 95% confidence interval exceeded the noninferiority margin of 20%.