In The Politics of Autism, I analyze the discredited notion that vaccines cause autism. This bogus idea can hurt people by allowing disease to spread. Trump has helped spread misinformation.
Foremost among the strategies researchers have devised to break through misgivings about vaccination is, essentially, scaring people into doing it. In 2015, Zachary Horne, a psychology professor at Arizona State University, divided 315 participants into three groups. The first group read a story about a child who contracted measles; looked at a picture of a child with measles, mumps, or rubella; and read warnings about the importance of vaccination. The second simply read statistics showing there is no link between vaccination and autism. The third read about an unrelated topic. The group exposed to the vivid anecdotes were more likely to change their attitude toward vaccines than the other two. Vaccine skeptics often tell frightening personal stories of injury; Horne did the same thing, but for diseases.
But other experts say adjusting attitudes is a fruitless exercise. Some evidence shows that giving people —including the vaccine-hesitant—correct information actually causes them to double down on their resistance, in a psychological concept known as the “backfire effect.” In a study similar to Horne’s, another group of researchers found that images of sick children only worsened parents’ misperceptions about the vaccine-autism link, and did not boost their intent to vaccinate their children.
Instead, this camp endorses a strategy called “direct behavior change.” Pediatricians might, for example, simply tell parents which vaccinations they’ll be performing during their child’s appointment, rather than ask them whether they’d like to vaccinate. According to research, parents are much more likely to avoid vaccinating if the pediatrician says something like, “What do you want to do about shots?” as opposed to, “Well, we have to do some shots.”