Social, institutional, and structural determinants of health behaviour change in an urban post-disaster setting: a qualitative case study from Palu City, Indonesia

Health promotion and education are essential for improving population health in post-disaster settings, yet evidence on how health behaviours evolve over time in urban recovery contexts remains limited, particularly in low- and middle-income countries. This study examined determinants of health behaviour change in post-disaster Palu City, Indonesia. A qualitative case study was conducted between January and June 2025 using interviews, focus groups, and observations with 28 purposively selected participants. Data were analysed inductively through iterative thematic analysis, with saturation ensuring analytic completeness. Five determinants were identified: risk perception, participatory education, social support and norms, trust in health services, and structural constraints. Risk perception initially drove engagement but declined over time, while participatory education and social support reinforced sustained practices. Trust shaped message acceptance and care-seeking behaviours, whereas economic hardship and limited access constrained long-term change. These findings show that health behaviour change is shaped by dynamic social, institutional, and structural interactions, extending social-ecological perspectives by highlighting temporal shifts in determinants and the mediating role of trust. Effective health promotion requires multilevel, context-sensitive strategies to sustain behavioural change.