Association Between Online Health Misinformation Susceptibility and Health Risk Behaviors and Vaccine Hesitancy: A Cross-Sectional Study Among Nurses in Greece

Background/Objectives: Online health misinformation is an emerging public health concern, as it may influence health behaviors and vaccination decisions. This study addresses how susceptibility to online health misinformation shapes nurses' health behaviors and attitudes toward vaccination. Methods: A cross-sectional study was performed in Greece using an online questionnaire in September 2025. Online health misinformation susceptibility was measured with the Health-Related Online Misinformation Susceptibility Scale. Health behaviors were measured by the Health Behavior Inventory–Short Form (HBI-SF), and vaccine hesitancy was assessed through the Vaccine Hesitancy Scale (VHS). Multivariable analyses were performed to determine the independent effect of vulnerability to misinformation after adjusting for possible confounding variables. Results: The multivariable linear regression analyses showed that susceptibility to online health misinformation was positively associated with diet scores (adjusted beta = 0.033, 95% confidence interval [CI]: 0.016–0.051, p < 0.001) and anger and stress score (adjusted beta = 0.065, 95% CI: 0.047–0.082, p < 0.001). The misinformation susceptibility was positively associated with higher levels of vaccine hesitancy. In particular, we found a positive association between misinformation susceptibility and lack of confidence (adjusted beta = 0.021, 95% CI 0.012-0.030, P < 0.001) and risk perception (adjusted beta = 0.032, 95% CI: 0.022–0.042, p = 0.001). Conclusions: Our findings suggest that higher susceptibility to online health misinformation is linked to poorer health behaviors and greater vaccine hesitancy.