Trust in institutions affects vaccination campaign outcomes.

Background: Trust is an important driver of various outcomes, but little is known about whether trust in institutions affects actual vaccination campaign outcomes rather than only beliefs and intentions.

Methods: We used nationally representative, individual-level data for 114 countries and combined them with data on vaccination policies and rates. We measured the speed of the vaccination campaign for each country using the estimated growth rate of a Gompertz curve. We then performed country-level regressions in the global sample and explored heterogeneity across World Bank development groups.

Results: Globally, higher trust in institutions significantly increased vaccination rates (p<0.01) and vaccination speed (p<0.01). The effect was strong in low- and middle-income countries but statistically not significant in high-income countries.

Conclusions: Our findings have implications for the design of vaccination campaigns for national governments and international organizations. The findings highlight the importance of trust in institutions when designing communication strategies around vaccination campaigns in low- and middle-income countries.