Recent measles outbreaks in the U.S. highlight the importance of maintaining high rates of immunization with the measles, mumps and rubella (MMR) vaccine
. However, little is known about what messages are most effective in overcoming the reluctance of some parents to vaccinate their children.
Parents were randomly assigned to receive one of four interventions representing strategies commonly used by public health agencies to promote vaccination:
- Information from the Centers for Disease Control and Prevention explaining the lack of evidence that MMR vaccine causes autism
- Textual information about the dangers of the diseases from the Vaccine Information Statement
- Images of children who have diseases prevented by MMR vaccine
- A dramatic narrative about an infant who almost died of measles from a CDC fact sheet; or to a control group.
Parents' beliefs and attitudes about vaccines were surveyed before and after the interventions. None of the messages increased parents’ intent to vaccinate, and some of them backfired. Parents who heard the CDC information debunking a supposed link between MMR vaccine and autism did have fewer misperceptions that vaccines cause autism. But compared to the control group, these parents’ intent to vaccinate decreased after hearing this message -- a reaction that was concentrated among the most vaccine-hesitant parents. In addition, messages intended to communicate the dangers of the diseases MMR prevents were found to increase misperceptions -- images of children who have the diseases increased parents’ reported misperceptions about MMR causing autism, while those who read a narrative about an ill child expressed more concern about side effects from the vaccine.
The researchers conclude additional research is needed to determine what messages would be more persuasive, such as more subtle narratives or messages that do not induce fear. According to the study authors, any approaches should be carefully tested before dissemination to assess their effectiveness, especially among skeptical populations.