Myths regarding the safety of vaccines are a huge barrier to promoting immunization. However, a study in the journal Vaccine reports - perhaps counterintuitively - that correcting these myths may actually contribute to vaccine hesitancy among skeptical groups, rather than raising intent to vaccinate.
In the new study, researchers from Dartmouth College in Hanover, NH, and the University of Exeter in the UK analyzed data collected from the 2012 Cooperative Congressional Election Survey in the US.
Respondents of the survey were randomly assigned to answer questions on one of three flu-related scenarios, with attached information on vaccination based on Centers for Disease Control and Prevention (CDC) materials:
- A control scenario with no attached additional information about flu or flu vaccines
- A danger scenario that presented information about the health risks posed by flu
- A correction scenario that informed respondents that they cannot contract flu from flu shots or live virus nasal spray.
The researchers found that 43% of respondents said the belief that the flu vaccine can give you flu is either "somewhat accurate" or "very accurate." When these respondents were given information correcting this myth, they reported they were less likely to continue supporting this belief or to believe that the flu vaccine is not safe.
What is interesting, however, is that among people with high levels of concern about vaccine safety, self-reported intention to vaccinate was reduced following receipt of the corrective information. Put simply: the information made some people less likely to vaccinate, even though the accurate information was persuasive enough to change their views on vaccine safety.
No significant effect from the corrective information was measured among participants who reported low concern about vaccine side effects at the start of the study.
Findings support previous studies assessing usefulness of corrective information
Co-author Brendan Nyhan, an assistant professor of government at Dartmouth College, says:
"Our findings suggest that corrective information can successfully reduce false beliefs about vaccines. However, that corrective information may unfortunately cause people with fears about side effects to bring those other concerns to mind and thereby reduce their intention to vaccinate.
We need to learn how to most effectively promote immunization. Directly correcting vaccine myths may not be the most effective approach."
Nyhan and his colleague Jason Reifler, a senior lecturer of politics at the University of Exeter, believe that the findings of the new study support those from previous studies the pair have conducted.
In one such study, published in 2010, Nyhan and Reifler conducted experiments investigating the extent to which corrective information in mock news reports is successful in reducing misperceptions about modern politics.
In that study, participants were randomly assigned to read articles (about the war in Iraq, tax cuts or stem cell research) that either included or did not include corrective information immediately after a false or misleading statement. The participants were then asked to answer a series of factual and opinion-based questions.
Nyhan and Reifler found in that study that corrective information not only fails to reduce misperceptions for some participants, but actually strengthens them among the groups most committed to their belief in those misperceptions.