An examination of factors beyond the 5C Model in COVID-19 Vaccine Uptake Decisions

A delay in accepting or a refusal of vaccination despite the availability of vaccination services is referred to as vaccine hesitancy. Vaccine hesitancy has gained increased attention, particularly since the outbreak of the COVID-19 pandemic. The most commonly used framework in studies of vaccine hesitancy and its determinants has been the 5C model. The 5C model posits that the five individual-level determinants influencing vaccine hesitancy are confidence, complacency, constraints, calculation, and a feeling of collective responsibility. However, other factors that may also be important in influencing vaccine hesitancy, such as sociodemographic and psychological determinants, have received less attention. Objectives: This study analyzed 1) the effectiveness of the 5C model in predicting the COVID-19 vaccination decision and 2) the association between COVID-19 vaccination decisions and the fear of being infected with COVID-19, attitude toward the media’s COVID-19 vaccination information, monetary incentives, political attitudes, perception of Hong Kong’s future, and attitude toward the vaccination advice of authorities (government officials and healthcare professionals). Methods: This study used data collected in an online questionnaire distributed from May 2022 to June 2022 during the fifth wave of the Omicron variants in Hong Kong. The questionnaire had 32 items measuring the COVID-19 vaccination status, demographic characteristics, the five determinants of the 5C model, and the following six additional factors: 1) fear of being infected with COVID-19, 2) attitude toward the media’s COVID-19 vaccination information, 3) monetary incentive, 4) political attitudes, 5) perception of Hong Kong’s future, and 6) attitude toward the vaccination advice of authorities. Results and Conclusions: For the 5C determinants, only confidence was significantly positively associated with COVID-19 vaccination, whereas complacency, constraints, and collective responsibility were associated when a relaxed p-value (p ≤ 0.25) was used. For the six additional factors, only attitude toward the media’s COVID-19 vaccination information was significantly positively correlated with vaccination status, and when a relaxed p-value (p ≤ 0.25) was used, a fear of being infected with COVID-19, political attitudes, and perception of Hong Kong's future was found to be associated. There was no evidence that calculation, monetary incentives, attitude toward the vaccination advice from authorities, or demographic characteristics were associated with COVID-19 vaccination decisions. The collinearity analysis among the 5C determinants and six additional factors suggested that the six new variables are additional determinants of vaccination decisions.