In this article, we examine the individual predictors that are responsible for accurate beliefs about the link between vaccinations and autism. We then show how these beliefs affect policy preferences about vaccines. We derive two hypotheses from motivated reasoning theory and test these on national survey data from Gallup and CBS News. Republicans were less likely to report accurate beliefs than Democrats. In addition, educational attainment modified the impact of party identification. The gap between Republicans and Democrats in likelihood of reporting accurate beliefs was largest among the most educated portion of the public. Finally, we show that accurate beliefs about vaccines, independent of statistical controls, are important predictors of policy attitudes about unvaccinated children attending public school and parental choice about the decision to vaccinate. We discuss the theoretical and practical significance of these findings.

Many Americans endorse misinformation about vaccine safety. This is problematic because those who do are more likely to resist evidence-based policies, such as mandatory vaccination for school attendance. Although many have attempted to correct misinformation about vaccines, few attempts have been successful. This study uses psychological correlates of vaccine misinformation acceptance to develop a novel misinformation correction strategy by tailoring provaccine messages to appeal to these psychological traits. For example, people with higher moral purity levels are more likely to view vaccines as contaminating the body, but messages highlighting disease via under-vaccination can use their higher moral purity to push them toward vaccine support. Using a large survey experiment ( N = 7,019) and a smaller replication experiment ( N = 825) of American adults, we demonstrate that interventions designed to appeal to people high in moral purity and needle sensitivity—two relatively understudied correlates of vaccine misinformation support—can also be targeted to effectively reduce vaccine misinformation endorsement. This study provides a better understanding of the psychological origins of misinformed political and policy attitudes, and it suggests a strategy for combating policy-related misinformation more generally, ultimately boosting support for evidence-based policies.

Using an original demographically representative survey, we estimate the determinants of public support for a set of supportive and punitive policies to combat the opioid epidemic among a sample of 2,131 Americans. Our findings indicate that individuals who attribute blame for the epidemic to the personal choices of individuals, conservatives and those high in racial resentment are consistently more likely to support punitive policies to combat the opioid epidemic and less likely to favour policies to support individuals with substance use disorders. Individuals who have a personal connection to someone struggling with opioid use disorder favour policies to support such individuals but have nuanced attitudes towards punitive policies. Importantly, we find overwhelming support for all supportive policies except supervised injection sites, while roughly 50% of our sample supported the set of punitive policy choices. Our research represents a significant step forward toward understanding public opinion about the opioid epidemic and policies to combat it.