Self-Efficacy As a Mediator between Functional Independence, Social Networks, and Dementia-Prevention Behaviors in Community-Dwelling Older Adults: A Cross-Sectional Study

Purpose: While capability and opportunity factors in dementia prevention have been extensively studied, the motivational mechanisms that translate these resources into behavior remain relatively underexplored. This study examined the mediating effect of self-efficacy on the relationships between instrumental activities of daily living (IADL), social networks, and dementia-prevention behaviors among community-dwelling older adults, guided by the capability, opportunity, motivation-behavior (COM-B) theoretical framework.Methods: A cross-sectional study was conducted with 205 community-dwelling adults aged 65 years and older residing in Gyeongsangnam Province, South Korea. Data were collected between July and September 2024 using validated instruments, including the Korean Instrumental Activities of Daily Living, Social Network Measurement Scale, General Self-Efficacy Scale, and Korean Health Behavior for Dementia Prevention Scale. Mediation analysis was performed using Hayes’ PROCESS macro (model 4) with bootstrap resampling (5,000 iterations) to estimate indirect effects, while controlling for demographic and health-related covariates.Results: Self-efficacy significantly mediated both the IADL–dementia-prevention behavior relationship (indirect effect, −0.33; 95% confidence interval [CI], −0.61 to −0.12) and the social network– dementia-prevention behavior relationship (indirect effect, 0.08; 95% CI, 0.002 to 0.19). The mediation models explained 40.7% and 48.5% of the variance in dementia-prevention behaviors, respectively. Bootstrap CIs confirmed significant partial mediation effects in both pathways.Conclusion: These findings provide empirical support for the COM-B model’s theoretical proposition that motivation serves as a critical bridge linking capability and opportunity factors to actual behavior. Nursing interventions should therefore integrate self-efficacy–enhancement strategies alongside traditional capability-building and opportunity-provision approaches to maximize the effectiveness of dementia-prevention programs for older adults.