Vaccination is the most effective method to prevent infectious diseases like coronavirus disease 2019 (COVID-19) and prompt herd immunity. However, herd immunity could be slowed or stalled if people hesitated to be vaccinated. This project aims to facilitate informed vaccination decisions. The research aims to illuminate how people’s vaccination decisions evolve in response to their social context. The project’s novelty is to follow participants over time to evaluate their real-world decision-making about vaccination. The project will advance the state-of-the-art on risk communication during crises and decision-making under uncertainty. The project will identify effective communication about COVID-19 vaccines that are understandable by, and applicable to, the public. The project could ultimately improve the immunization rate of the population to pass the threshold for herd immunity and the collective health benefits of immunization.

The project entails four tasks that will advance the understanding of human vaccination decision-making under risk and uncertainty. (1) Develop communications about the COVID-19 vaccines that are experimentally varied in completeness, transparency, and correctness by leveraging the standards of risk communication in the health domain. (2) Evaluate the effectiveness of proposed communications in enhancing people’s knowledge of COVID-19 vaccines and informing their vaccination decisions. (3) Examine the effectiveness of proposed communications on informing peoples’ vaccination decisions in real-world application settings. (4) Investigate how people respond to uncertainties of different situations in order to understand how vaccination decisions evolve throughout the current vaccination campaign.