Health Decisions Under Uncertainty: The Roles of Conspiracy Beliefs and Institutional Trust

Research on vaccination hesitancy has been extensive, but the role of information processing in decision making still needs to be explored. The study examines the alignment between parents’ COVID-19 vaccination intentions and actual behavior, focusing on the impact of different kinds of information processing on the consistency or inconsistency of these behaviors. It analyzes parents’ reliance on health information sources, and education levels, with institutional trust, ability to critically evaluate conspiracy theories and scientific knowledge as moderators. A total of 1118 Israeli parents participated in digital surveys and were classified into the following 4 groups based on their initial vaccination intentions and actual behaviors: (1) consistent—pro-vaccine and vaccinated; (2) inconsistent—pro-vaccine but unvaccinated; (3) inconsistent—anti-vaccine but vaccinated; and (4) consistent—anti-vaccine and unvaccinated). The results show that consistent parents process information using system 1, i.e., heuristic information processing, reliance on health information sources, moderated by institutional trust and education. However, inconsistent parents used systems 1 and 2, namely heuristic–systematic information processing, influenced by knowledge of COVID-19 and the ability to assess conspiracy theories critically.