Vaccination decisions under risk: experimental evidence from the COVID-19 pandemic

Abstract We examine how risk preferences influence vaccination decisions and subsequent behavior in a pandemic context. Using data from 2,701 individuals from seven European countries, we employed an incentivized ‘virus risk elicitation task’, adapted from the bomb risk elicitation task, to elicit individual risk preferences in a health-related context. In the first part of the experiment, all participants faced a risk of infection without the option of vaccination. In the second part, some participants were offered a vaccination option that reduced potential losses from infection. We found that most participants were risk-averse and that there was an inverse U-shaped relationship between risk preferences and vaccination uptake: individuals with risk preferences closer to neutrality were more likely to opt for vaccination. Among participants who chose vaccination, we observed an increase in social interaction, which is consistent with risk compensation behavior. These results provide evidence on the relationship between risk preferences, vaccination decisions, and post-vaccination behavior, offering insights into the drivers of vaccine hesitancy and informing the design of future public health strategies.