Abstract
Classical theories within health psychology analyze individuals' decisions about whether to engage in protective behavior such as vaccination during a health emergency as guided by trade-offs about personal risks and benefits. Yet, vaccinations involve a clear collective action component, where individuals can protect others by getting vaccinated, independently of personal benefits. Following recent research, we argue that individual differences in motivation to engage in collective action should influence vaccination decisions during the most significant health emergency of the 21st century, the COVID-19 pandemic, beyond predictors proposed by classical theories. We test this argument using nationally representative survey data from 380,516 individuals combined with registry data on all 4.8 million vaccinations performed in Denmark during the COVID-19 pandemic. Using this unique data infrastructure, we compare the predictive power of classical psychological predictors of protective behavior with psychological measures of individual differences in collective action motivation. Results demonstrate that collective action motivation is a stronger predictor of initiating vaccination, completing vaccination, and receiving a booster than classical predictors, and also shapes vaccination uptake among respondents’ children. Furthermore, high levels of collective action motivation offset negative effects of personal considerations that would otherwise deter vaccine uptake, both in whether and how quickly individuals get vaccinated. These findings inform prerequisites for successful vaccination campaigns during major health crises and how governments and authorities can facilitate them.