Naturalistic Evaluation of HeadGear: A Smartphone App to Reduce Depressive Symptoms in Workers

Mobile health (mHealth) apps have the potential to expand access to evidence-based interventions for mental health conditions, including depression. HeadGear was developed to prevent depression and improve well-being among the working population and was associated with significant positive effects in an efficacy trial. This study presents the results from a naturalistic trial intended to evaluate real-world usage of the app. We examined the naturalistic use of HeadGear between March 2019 and March 2022, using app analytic data, in-app event data, and surveys assessing depressive symptoms, well-being, and work performance repeated at 30-day intervals over 5-month app usage. During the observation period, HeadGear was widely disseminated to the public, and downloaded 26,455 times. Of those who downloaded the app, 12,995 completed baseline. The mean age of users was 38.23 (SD = 12.39) and 60% were women. Approximately one in four met criteria for probable depression at baseline. Depressive symptoms showed consistent improvement at all time points (Cohen's d ranging from 0.24 at 1 month to 0.13 at 5 months). A similar pattern emerged for well-being. Work performance showed improvement to 2-month follow-up only. The strongest change was found for those with greater symptom severity at baseline, and those with high app engagement. Attrition at follow-up points was high. Findings regarding the real-world use of HeadGear are promising and highlight the use of such apps among those with higher symptom severity (despite the intended use of the app as a prevention tool). Further work is required to tailor mHealth apps to reach their full potential through an enhanced understanding of the utility of individual features for effectiveness and engagement.