Given the relationship between vaccination hesitancy and vaccine-preventable disease outbreaks, it is essential to investigate the cognitive processes that lead to vaccine hesitancy development, particularly among adolescents’ parents. The study investigated how vaccine hesitancy and intent to vaccinate are associated with six decision-making factors: base rate neglect, conjunction fallacy, sunk cost bias, present bias, risk aversion, and information avoidance using secondary analysis of baseline data from a two-phase randomised trial on human papillomavirus. Through an Amazon online poll, researchers recruited 1,413 individuals in the United States who had at least one daughter aged 9–17.

A set of brief questions were used to assess vaccine reluctance, desire to vaccinate, and vulnerability to cognitive biases. The total examined sample included 1,400 individuals. The majority of participants were white (74.1%), female (71.6%), married (75.3%), and had a college or graduate/professional degree (88.8 percent ). Vaccine reluctance may be related with the conjunction fallacy, sunk cost bias, information avoidance, and present bias. The intention to vaccinate may be linked to information avoidance. These findings imply that cognitive biases have a role in the development of parental vaccination apprehension and vaccine-related behaviour.