Beyond risk perception: Capability, opportunity, and motivation as determinants of heat- protective behaviour among urban residents

Extreme heat poses increasing public health risks due to climate change, yet adoption of protective behaviours remains suboptimal. This study applied the Capability, Opportunity, Motivation, and Behaviour (COM-B) framework to identify correlates of heat-protective behaviour during extreme heat episodes, examining the relative contributions of capability, psychological and social factors. A cross-sectional survey of 1,508 urban residents in three Spanish cities was conducted in July 2025 following several summer heat wave episodes. Participants reported frequency of seven protective behaviours (hydration, staying indoors, using fans/air conditioning, seeking cool spaces, modifying routines, checking on vulnerable others) and completed measures of capability (knowledge, confidence, resource availability, perceived effectiveness), opportunity (housing characteristics, social support, institutional resources), and motivation (worry, perceived severity, intention, attitudes, self-efficacy). Hierarchical multiple regression examined incremental contributions of COM-B components. Participants reported moderately high protective behaviour adoption. The full COM-B model explained 28% of behavioural variance, with motivation and capability contributing roughly equally, and opportunity showing smaller effects. Strongest individual predictors were intention, worry, perceived severity, positive attitudes towards self-protective actions, and social support. Women and younger adults reported higher protective behaviour. Heat-protective behaviour is driven by both psychological motivation and capability, with social support playing an important facilitating role. Effective interventions must be comprehensive, addressing emotional engagement and positive attitudes towards self-protection while ensuring universal access to cooling resources and leveraging community networks. The relative importance of COM-B components might vary by behaviour type and context, requiring tailored intervention approaches.