Educational background and vaccination beliefs in the Netherlands: A Bayesian Evidence Synthesis from four studies

Background Although studies repeatedly show that higher educated individuals uphold more positive beliefs about vaccines than their lower educated counterparts, emerging evidence suggests that vaccine skepticism can also be found among highly educated individuals in certain contexts. Given these divergent perspectives on the relation between educational background and vaccine beliefs, the present study investigated (a) the magnitude of educational differences in vaccination attitudes and (b) educational differences in changes in vaccination attitudes over time after the COVID-19 pandemic. Methods We used survey data from nine samples across four Dutch studies ( n = 23.174), covering different populations and vaccinations (e.g., childhood vaccination, COVID-19 vaccination), with most data collected after the peak period of the COVID-19 pandemic. For each sample, we used various regression techniques to model vaccine attitudes predicted by (a) educational background and (b) time across educational groups. Sample estimates were translated into Bayes Factors (BF) and Posterior Model Probabilities (PMPs), which quantify how strongly observed estimates support predefined hypotheses. Findings were synthesized by aggregating BFs and PMPs using Bayesian Evidence Synthesis (BES): a novel statistical approach to synthesize findings. Results Consistently across samples, higher educated respondents reported more positive vaccine attitudes than lower educated respondents, but the magnitude of these differences varied. At the aggregate level, the data showed more support for small than for moderate educational differences. However, longitudinal samples consistently showed more support for moderate educational differences in attitudes towards vaccination. The data showed strong support for stable attitudes over time for both higher and lower educated respondents. Conclusions The substantial educational differences in vaccine attitudes observed in longitudinal data warrant targeted communication strategies on vaccine information and outreach to lower educational groups. Yet, the observed heterogeneity underscores the importance of a nuanced perspective on the role of educational background in vaccine attitudes.