Usability, Acceptance, and Effectiveness of a Coach-Guided, App-Based Mental Health Intervention: The beWell Tirol Pilot Study

Background Mental illness is highly prevalent and associated with significant public health costs. Despite this, less than half of those affected receive treatment, often due to barriers such as stigma and accessibility. Internet-based interventions (IBIs) have shown promise in improving well-being and reducing psychological distress, yet many lack personalization and sufficient guidance. Addressing these limitations, beWell Tirol integrates cognitive behavioral content, individualized task selection, and on-demand coaching within a self-determined, app-based format, allowing users to autonomously select and adapt exercises according to their individual needs and preferences. Objective This study evaluates the usability, acceptance, and effectiveness of a digital mental health intervention, "beWell Tirol," a 4-month app-based program accompanied by a coach, targeting individuals experiencing high psychological distress. Methods A total of 25 participants with above-average psychological distress completed the 4-month intervention. The program included a selection of cognitive behavioral therapy-based exercises, which were available via the app, as well as bi-weekly coaching sessions. Assessments were conducted at baseline, post-intervention, and three months post-intervention, measuring usability (System Usability Scale, SUS) and satisfaction (primary outcomes), as well as psychological distress, resilience, self-efficacy, stress coping strategies, emotion regulation, and quality of life (secondary outcomes). Statistical analyses included repeated measures ANOVA and t-tests. Results The intervention demonstrated excellent usability (SUS score: M = 91.8, SD = 7.5) and high satisfaction. Significant improvements were observed in resilience, self-efficacy, psychological distress (Perceived Stress Scale, Brief Symptom Inventory), emotion regulation, and multiple dimensions of quality of life (p < .05). These improvements were partially sustained at follow-up. Conclusion The program was well accepted, demonstrated high usability, and was effective in improving mental well-being. The results support the feasibility and effectiveness of a coach-guided, self-determined digital intervention for promoting mental health. Future research should explore larger samples, including control groups. Trial registration ClinicalTrials.gov, NCT07300410, 09/12/2025, Retrospectively registered