Refugees face substantial mental health challenges, but often underuse available support due to stigma, information gaps, and cultural barriers. Through two large-scale randomized controlled trials involving Ukrainian refugees in Germany, we evaluate innovative digital interventions designed to increase uptake of mental health services. We find that videos featuring relatable patient testimonials significantly enhance hotline utilization, whereas peer-to-peer dissemination is limited. Surprisingly, explicit prompts to encourage peer-to-peer dissemination via social media reduced overall engagement, uncovering unexpected complexities in leveraging digital peer influence. We build and calibrate a simple social diffusion model illustrating trade-offs between targeting refugees more aware of mental healthcare needs and more likely to call for help, relative to dissemination in the wider refugee population. (Joint work with Alexandra Avdeenko, Luc Behaghel, Esther Duflo, Andreas Ette, Yagan Hazard, Alexander Moldavski, Nicolas Rüsch, and C. Katharina Spiess.)
