Working Paper: NBER ID: w26772
Authors: Mengcen Qian; Shinyi Chou; Ernest K. Lai
Abstract: Since Wakefield et al. (1998), the public was exposed to mixed information surrounding the claim that measles-mumps-rubella vaccine causes autism. A persistent trend to delay the vaccination during 1998–2011 in the US was driven by children of college-educated mothers, suggesting that these mothers held biases against the vaccine influenced by the early unfounded claim. Consistent with confirmatory bias, exposures to negative information about the vaccine strengthened their biases more than exposures to positive information attenuated them. Positive online information, however, had strong impacts on vaccination decisions, suggesting that online dissemination of vaccine-safety information may help tackle the sticky misinformation.
Keywords: MMR vaccine; autism; confirmatory bias; health decisions; vaccination rates
JEL Codes: I12; I18; I26
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| negative information exposure (D83) | biases against the MMR vaccine (J16) |
| positive information exposure (D83) | biases against the MMR vaccine (J16) |
| biases against the MMR vaccine (J16) | delay in MMR vaccination (C41) |
| negative information exposure (D83) | delay in MMR vaccination (C41) |
| positive information exposure (D83) | delay in MMR vaccination (C41) |
| educational gap in vaccination rates (I24) | biases against the MMR vaccine (J16) |