Association of Moral Values with Vaccine Hesitancy

"[T]here are few evidence-based strategies to address vaccine hesitancy and even fewer based on quantitative evidence..."

The impetus behind this study is that attitudes towards vaccines may be rooted in deeper intuitions that guide individual decisions, as evidenced by the apparent resistance of vaccine attitudes to messaging/educational interventions. Past research has demonstrated that framing persuasive messages using the moral foundations that underlie people's attitudes and judgements can successfully change attitudes. The present study, which consists in 2 correlational studies, shows that it is necessary to understand how underlying morals, not just attitudes, differ by hesitancy type to develop interventions that work with individual values and that, ultimately, get at the hesitancy that can contribute to outbreaks of vaccine-preventable disease.

Moral foundations theory proposes that a set of innate intuitions lead humans to certain emotional responses (for example, approval or disapproval) to particular interpersonal events. Attitudes towards vaccines may be similarly based in such intuitive processes. Six foundations have been proposed: care/harm, authority/subversion, loyalty/betrayal, liberty/oppression, purity/degradation, and fairness/cheating. The extent to which each of the 6 moral foundations is used in moral judgments and decision-making varies by individual and across cultures.

This article presents the results of direct investigations into the association of the values-based foundations of moral foundations theory with parental vaccine hesitancy.

• The first study included 1,007 consenting United States (US) parents who met eligibility criteria and answered an online survey about moral foundations and vaccine attitudes. Of the respondents, 73.0% were classified as low hesitancy according to their Parent Attitudes about Childhood Vaccines score, while approximately 11% were classified as medium hesitancy, and 16% were classified as high hesitancy. In short, the researchers found:
  • Several distinct values are associated with parental vaccine hesitancy. However, more foundations are significantly associated with high hesitancy than with medium hesitancy. For medium-hesitancy parents, the only association is high endorsement of purity, while high hesitancy is associated with high endorsement of both purity and liberty and low endorsement of authority.
  • The influence of different generational values may also prove important, as younger high-hesitancy parents are more likely to highly endorse liberty.
  • The strengths of emphasis on harm and fairness were not statistically significantly (P < 0.05) associated with the degree of vaccine hesitancy.
  • The strength of the associations is not impacted by either gender or political ideology.
• A second study, conducted independently of the first, validated the main findings of study 1. The final sample for analysis included 464 consented parents who were at least 18 years of age, resided in the US, and had at least one child. This study found, in short, that:
  • Overt concerns cited by vaccine-hesitant parents are directly linked to purity and liberty moral foundations.
  • High emphasis on the purity and liberty foundations is associated with vaccine beliefs directly tied to purity foundation violations (for example, vaccines contain poisons and toxins, while diseases like measles are natural).
  • High emphasis on the liberty foundation is associated with vaccine beliefs directly tied to liberty foundation violations (for example, vaccine mandates violate civil liberties and are excessive government control).

Although it is not possible to assess causality between moral foundations and vaccine hesitancy due to the cross-sectional nature of these studies, the researchers suggest that future interventions in vaccine attitudes could be framed using the moral foundations associated with medium or high hesitancy. Messages could avoid a backfire effect by presenting vaccine effects and importance couched in purity and liberty foundation-stimulating terms.

For example, an intervention framed in terms of the purity foundation might read, "Boost your child's natural defences against diseases! Keep your child pure of infections - Vaccinate!" This message might show a picture of a child with measles. An intervention framed in terms of the liberty foundation might read, "Take personal control of your child's health! Vaccinations can help your child and others be free to live a happy and healthy life", along with pictures of children playing. Messages could be displayed at public schools, libraries, doctors' offices, and on the internet. Immunisation programmes could also integrate such an approach into communications training for their personnel and educational modules for clinicians, as well as the development of foundation-framed talking points for quick reference.

The researchers conclude that this morals-based approach can be applied to other health decisions and may provide a standardised, yet easily adaptable approach for public health interventions.