Predictors of the willingness to receive the third dose of COVID-19 vaccine based on the Health Belief Model: A cross-sectional study in South Khorasan province.

Coronavirus disease 2019 (COVID-19) infections have re-emerged in several countries due to reduced levels of antibodies provided by vaccines or the rapid emergence of viral variants, such as Alpha, Beta, Gamma, and Delta. A considerable supplementary intervention is recommended, including an additional dose of vaccination. The present study aimed to assess the predictors of the willingness to receive the third dose of the COVID-19 vaccine based on the Health Belief Model (HBM) constructs among people referring to health centers in South Khorasan province. In this cross-sectional-analytical study, 283 people over 18 years old in South Khorasan province were randomly selected using the multi-stage cluster sampling method. The data were collected using a researcher-made questionnaire, including demographic information and health status, knowledge about COVID-19, and the third dose of the vaccine, as well as a questionnaire according to the HBM constructs, which was completed through self-report methods. Finally, the data were analyzed using the Chi-square test and multivariate logistic regression analysis. The mean age of the study participants was 36.57±11.56 years (range of 18-55). The results of multivariate logistic regression analysis demonstrated that gender (P=0.012), marital status (P=0.038), occupation (P=0.013), perceived severity (P=0.005), and cues to action (P=0.018) had a significant direct effect, while perceived barriers (P=0.010) had a significant inverse effect on the willingness to accept the third dose of the vaccine. Moreover, the predictor variables explained about 67.7% of the willingness to receive the third dose of the vaccine. The current study suggested that enhancing the perceived severity of COVID-19, along with healthcare providers' recommendations to receive the vaccine and reducing perceived barriers, can effectively encourage individuals to receive the third dose of the COVID-19 vaccine. These findings can be utilized to develop interventions aimed at promoting the uptake of the booster dose of the COVID-19 vaccine.