Abstract
Asylum seekers from Afghanistan face heightened risks of post-traumatic stress disorder (PTSD), depression, and anxiety due to severe pre-migration trauma compounded by post-migration stressors in host countries. However, structural, linguistic, and cultural barriers severely restrict access to mainstream mental health services in Germany. This randomized controlled trial (RCT) evaluated the efficacy of a culturally adapted, smartphone-delivered mental health application ("Roshani") tailored for Dari- and Pashto-speaking Afghan asylum seekers. A total of 164 adult participants residing in initial reception centers across North Rhine-Westphalia were randomly assigned to either the 6-week digital intervention group (n = 82) or a waitlist control group receiving treatment-as-usual (n = 82). Primary outcomes were depressive symptoms measured by the Patient Health Questionnaire-9 (PHQ-9) and PTSD symptoms measured by the PTSD Checklist for DSM-5 (PCL-5), assessed at baseline, post-intervention (week 6), and 3-month follow-up (week 18). Intention-to-treat linear mixed-effects models revealed significant group-by-time interaction effects favoring the intervention group, with moderate-to-large effect sizes for depression (Cohen's d = 0.68) and PTSD symptoms (Cohen's d = 0.59) at post-treatment, which were sustained at follow-up. Secondary outcomes demonstrated marked improvements in psychological well-being and reductions in somatic distress. High engagement was facilitated by audio-integrated features addressing varied literacy levels and cultural idioms of distress. These findings demonstrate that culturally adapted digital interventions can effectively bridge critical mental healthcare gaps for newly arrived displaced populations, offering a scalable, low-threshold supplementary intervention within host-country reception infrastructure.