The political component of COVID-19 vaccine choice: Results from a conjoint experiment

Prior research highlights the role of efficacy, vaccine safety, and availability in vaccine hesitancy. Research is needed to better understand the political driving forces behind COVID-19 vaccine uptake. We examine the effects of the origin of a vaccine, and approval status within the EU on vaccine choice. We also test if these effects differ by party affiliation among Hungarians.

We use a conjoint experimental design to assess multiple causal relationships. Respondents choose between two hypothetical vaccine profiles randomly generated from 10 attributes. The data were gathered from an online panel in September 2022. We applied a quota for vaccination status and party preference. Three hundred twenty-four respondents evaluated 3888 randomly generated vaccine profiles.

We analyse the data using an OLS estimator with standard errors clustered by respondents. To further nuance our results, we test for task, profile, and treatment heterogeneity effects.

By origin, respondents prefer German (MM 0.55; 95% CI 0.52-0.58) and Hungarian (0.55; 0.52-0.59) vaccines over US (0.49; 0.45-0.52) and Chinese vaccines (0.44; 0.41-0.47). By approval status, vaccines approved by the EU (0.55, 0.52-0.57) or pending authorization (0.5, 0.48-0.53) are preferred over unauthorised ones (0.45, 0.43-0.47). Both effects are conditional on party affiliation. Government voters especially prefer Hungarian vaccines (0.6; 0.55-0.65) over others.

The complexity of vaccination decisions calls for the usage of information shortcuts. Our findings demonstrate a strong political component that motivates vaccine choice. We demonstrate that politics and ideology have broken into fields of individual-level decisions such as health.