Social norms, the informal rules that influence behavior, play essential roles in shaping people's behavior. Community-based norms-shifting interventions (NSIs) identify gender and other social norms linked to unhealthy behaviors and implement activities to promote collective change by encouraging communities to reflect on and question these norms. Though NSIs are gaining international traction in social and behavior change programming for health promotion, how change occurs needs to be clearly understood in African and other contexts. To build understanding and guidance for future NSI design, the applied-research Passages Project and collaborating non-governmental organizations in West and Central Africa conducted realist evaluations of four NSIs focused on adolescent/youth sexual and reproductive health, operating in Democratic Republic of Congo, Niger, and Senegal. The evidence base for the realist synthesis came from four quasi-experimental outcome evaluations and 19 rapid implementation studies, which confirmed the four program Theories of Change. The synthesis findings identified eight norms-shifting mechanisms common across NSIs: information provision; dialogical, experiential approaches; role modeling; safe spaces; within-community meetings; planned diffusion; cross-community meetings of change agents; and community-service linkages. NSIs directly, at times indirectly, engaged reference groups that uphold norms, explaining their theoretical roles operationally. These findings led to middle-range theory showing how NSI activities, mechanisms, and reference group engagement should, over time, lead to norms-shifting outcomes. Design implications include developing a fuller understanding of how program components, as norms-change mechanisms, lead to effects; being deliberate about when and how to engage reference groups; and recognizing systems complexity and the subsequent need for NSI implementation elasticity.
Keywords: West Africa; adolescents and youth; norms shifting interventions; realist synthesis; social and behavior change; social norms.