Gender-based violence (GBV) is prevalent in Accra's slums, with limited psychosocial support services available for survivors. A randomized controlled trial was conducted with 200 participants randomly assigned to either a control group (no intervention) or an intervention group (psychosocial support). Participants in the intervention group reported a significant increase in trust levels by 15% compared to those in the control group, indicating improved engagement and efficacy of support services. Psychosocial support interventions significantly enhance retention rates and trust levels among GBV survivors in Accra's slums. Expanding psychosocial support services in collaboration with local organizations is recommended to further improve outcomes for GBV survivors. Gender-based violence, Slum communities, Psychosocial support, Retention rates, Trust levels Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.