Testing a scalable web and smartphone based intervention to improve depression, anxiety, and resilience: A randomized controlled trial

Psychological interventions targeting wellbeing can reliably increase wellbeing and decrease depressive symptoms. However, only a handful of studies have implemented wellbeing interventions online, and those studies have largely done so in a way that prioritizes experimental control over realism and scalability. We sought to take existing wellbeing interventions with established efficacy and to evaluate their impact when translated into a format that is publicly accessible, scalable, and designed with the goal of engaging users. Participants in this fully online trial were first-time registrants of the Happify platform, a fully automated web and mobile wellbeing intervention grounded in positive psychology, cognitive-behavioral therapy, and mindfulness-based stress reduction, which has offered wellbeing programs to over 3 million registrants to date. Consenting participants were randomly assigned to access the full Happify platform or a psychoeducation comparison condition and further categorized by their usage during the study: recommended usage (a minimum of 2-3 activities per week) or low usage (usage less than the recommended level). Participants were assessed on depressive symptoms, anxiety symptoms, and a composite measure of resilience at baseline and 8 weeks later. Participants who used Happify at the recommended level reported fewer depressive and anxiety symptoms and greater resilience after 8 weeks than participants who used Happify at a low level or participants who used the psychoeducation condition at any level. The Happify group also experienced greater rates of reduction in depression and anxiety symptom severity category, and had a greater net benefit (% users who improved minus % users who deteriorated), compared to the other groups. The results of this study suggest a successful first attempt at implementing and scaling a comprehensive package of lab-tested wellbeing interventions without losing efficacy.