Psycho-behavioural factors influencing COVID-19 vaccine hesitancy among Korean adults: The moderating role of age.

Aims: This study aimed to identify the psycho-behavioural factors influencing coronavirus disease 2019 (COVID-19) vaccine hesitancy among Korean adults. We examined the primary effects of eHealth literacy, social responsibility and self-efficacy on COVID-19 vaccine hesitancy using the information-motivation-behavioural skills (IMB) model. The moderating effect of age on the relationship between psycho-behavioural factors and COVID-19 vaccine hesitancy was also examined.

Design: The study used a cross-sectional survey design.

Methods: An online survey was completed by 500 Korean adults (253 men and 247 women) aged 20-60 years. Data collection took place in May 2021. The constructed hypothetical model for eHealth literacy, social responsibility, self-efficacy and age was evaluated using partial least squares structural equation modelling (PLS-SEM).

Results: eHealth literacy, social responsibility and self-efficacy had significant negative effects on COVID-19 vaccine hesitancy. Age had a significant moderating effect on COVID-19 vaccine hesitancy. The moderating effects of age on the relationship between eHealth literacy and COVID-19 vaccine hesitancy and between social responsibility and COVID-19 vaccine hesitancy enhanced the explanatory power by high effect size. The overall fitness of the hypothetical model was good. The standardized root mean square residual value was 0.007, which explained 18.5% of the COVID-19 vaccine hesitancy.

Conclusion: To reduce COVID-19 vaccine hesitancy among Korean adults, a strategic approach that considers age should be adopted to enhance eHealth literacy, social responsibility and self-efficacy.

Impact: The findings of this study suggest that providing correct health information online related to the COVID-19 vaccine is likely to be effective in decreasing COVID-19 vaccine hesitancy in older individuals, whereas inspiring a sense of social responsibility is more likely to be effective in younger individuals. These strategic nursing interventions could contribute to improving COVID-19 vaccination rates among Korean adults.