Diffusion of an Effective Social and Behavioral Change Intervention to Prevent Intimate Partner Violence and Enhance Gender-Equitable Norms in Nepal.

Social norms approaches to intimate partner violence (IPV) prevention are a growing evidence-based practice, but assessment of impact diffusion beyond direct beneficiaries is still relatively rare. We examined the sustained impact and diffusion of the Change Starts at Home (Change) intervention with a sample of 1181 married adults in Nepal's Gandaki province. Timepoints included baseline, midline, endline, and 6-month follow-up. Difference-in-difference analyses assessed change in IPV, social norms, and secondary outcomes for two intervention conditions-(1) Listening, Discussion, and Action Group members (LDAG condition) and (2) residents of the community in which LDAGs were present (community condition)-relative to adjacent community residents (condition 3) where no core intervention activities took place. LDAG and community women reported sustained decreases in IPV (27% and 21%, respectively) at follow-up, with significant improvements in descriptive norms, gender equitable attitudes, relationship quality, and communication (for both groups) and injunctive norms, leadership, anti-violence advocacy, in-law violence, financial and sexual decision-making, and diffusion (for LDAGs). The intervention showed little impact on LDAG and community men, in part due to improvement across all conditions. Exposure to other programming unrelated to Change was also detectable, especially among men and to a lesser degree women, in the adjacent and community groups. Change may be effective at reducing IPV, improving associated norms, and extending programming benefits beyond those intentionally targeted. The general lack of intervention impact among men requires further investigation, but with benefits among women persisting at least 6 months post-intervention, replication, and cost-effective analyses are warranted.