Emotion regulation and social information processing as targets of a guided selective prevention app for emerging adults with a history of adverse childhood experiences: A randomised controlled trial.

Background: Adverse childhood experiences (ACEs) are associated with increased risk for psychopathology and reduced psychosocial functioning across the life course. However, digital selective prevention targeting individuals with a history of ACEs remains scarce. Impairments in emotion regulation and social information processing were confirmed as mechanisms linking ACEs with mental health and potential targets for interventions. This randomised controlled trial evaluated the uptake, efficacy, and differential component effects of the guided FACE app, a theory-based preventive intervention for emerging adults with self-reported ACEs that targets these mechanisms. Methods: Emerging adults (18-24 years) reporting at least one ACE category in a population-based cohort were invited to participate. Of 1514 eligible individuals, 167 (11%) enrolled and were randomised to immediate access to the FACE app or care as-usual with minimal intervention (CAU-MI). The 10-week intervention comprised two transdiagnostic components delivered in a cross-over design: Self- and Emotion Regulation (SER) and Social Skills and Social Information Processing (SSIP). Primary outcomes were resilience and well-being. Secondary outcomes included self-efficacy for managing emotions, social problem-solving, fear of negative evaluation, social avoidance, and self-esteem. Ecological momentary assessments captured real-life affect, burden, resilience, and social distress. Linear mixed models were applied under intention-to-treat and per-protocol principles. Results: Linear mixed models showed significant improvements over time (intervention and CAU-MI) in resilience, self-esteem, self-efficacy for managing emotions, adaptive problem-solving, momentary positive affect. Group × time interaction effects in favour of the app compared to CAU-MI emerged for some more proximal mechanism-related outcomes: self-efficacy for managing emotions, fear of negative evaluation and negative problem orientation but not for resilience and well-being, which were already at normative levels at baseline. Effects were largely maintained at follow-up. Improvements were stronger and more consistent following the SER compared to the SSIP component. Average time of app use was three hours. Conclusions: The FACE app did not improve the primary distal outcomes resilience and well-being beyond the CAU-MI condition. Nevertheless, the FACE app demonstrated modest but consistent improvements in proximal mechanisms associated with ACE-related vulnerability. Findings support the relevance of targeting emotion regulation and social-cognitive processes in digital selective prevention. However, limited uptake highlights challenges in active recruitment of unselected high risk populations and underscores the importance of integrating preventive apps into stepped-care or blended care models. Trial registration: ClinicalTrials.gov NCT05824182.