Abstract
Adolescents across the globe experience increasing demands for care, and the mental health of Polish and Ukrainian youth is especially concerning, due to ongoing war and displacement. This study explores the acceptability, feasibility, and short-term effects of a digital, self-guided single-session intervention (SSI) for improving the mental health of Polish and Ukrainian youth, including Ukrainian refugees in Poland. A non-randomized, open pilot trial was conducted from March to June 2024, involving youth aged 10-18 years from Poland and Ukraine. Participants completed an SSI after cultural adaptations and translation into Polish and Ukrainian. Measures assessed hopelessness, self-hate, agency, perceived control, and acceptability. Statistical analyses included paired t-tests and effect size calculations to examine intervention effects. Among 176 Polish and 139 Ukrainian youth who began the intervention, completion rates were 80.7% and 62.6%, respectively. Polish participants exhibited significant improvements in hopelessness, self-hate, perceived control, and agency, while Ukrainian youth showed moderate improvements in perceived control but limited change in other mental health indicators. Acceptability ratings were high across all youth. Findings suggest SSIs hold potential as a scalable option for mental health care. However, the varied outcomes across the two groups highlight the need for further refinement, especially for displaced youth.