2016 Gatlinburg Conference Poster
PS-61
Title: Beliefs about Causes of Developmental Delays and Vaccine Hesitancy among Parents of Children with and without Autism
Spectrum Disorder
Authors: Robin P. Goin-Kochel, Sarah S. Mire, Leandra N. Berry, Lauren R. Dowell, Charles G. Minard, Danielle Guffey, Leila C.
Sahni, Rachel M. Cunningham, Julie A. Boom
Introduction: Evidence suggests that nearly 42% of parents of children with autism spectrum disorder (ASD) believe that
vaccines played some causal role in their child's condition1. However, little is known about vaccine hesitancy in this group and its
relation to parents' beliefs about causes of ASD. The purpose of this study was to (a) assess parents' beliefs about causes of their
children's developmental delays and vaccine hesitancy among parents of children with ASD and children for whom ASD was ruled
out, (b) examine potential relationships between parents' attributions for their children's diagnoses and vaccine hesitancy, and
(c) determine if ASD and non-ASD groups differ in terms of their attributions for their children's diagnoses, etiological beliefs, and
vaccine hesitancy.
Methods: Data were collected from 89 parents of children who had been seen at the Autism Center at Texas Children's Hospital
and enrolled in a research registry (child's M age = 7.3 years, SD = 3.1; 78% male). Families who had agreed to be contacted
about new studies were mailed packets that contained a cover letter, a Parent Attitudes About Childhood Vaccines questionnaire
(PACV; measure of vaccine hesitancy), a Revised Illness Perception Questionnaire (IPQ-R; measure of attributions about
children's diagnoses and etiological beliefs), and a demographic form. Clinical diagnoses (ASD or not) were extracted from the
electronic medical record by one co-author and validated by a second. Summary statistics were compared between diagnosis
groups using two-sample t-tests or Fisher's exact test. A multiple logistic regression model was used to estimate odds ratios for
each response variable (belief that vaccines caused the child's developmental difficulties, vaccine hesitancy) with 95% confidence
intervals. Variables significant at the 0.20 level in the univariable analysis were included in both regression models adjusting for
diagnostic group (ASD or not).
Results: Overall, 20/87 (23%, 95% CI: 15, 33) of the parents believed that toxins in vaccines caused their child's developmental
difficulties, while 21/89 of the parents (24%, 95% CI: 15, 34) were vaccine hesitant (PAC-V ≥ 50). Parents of children with ASD
were significantly more likely to believe that vaccines contributed to their child's developmental difficulties (28% vs. 5%, p =
0.03). Adjusting for age and child's gender, the odds of believing vaccines caused the child's developmental difficulties were 7.3
(95% CI: 0.9, 60.8) times greater among parents of children with ASD compared to parents of children without ASD. Parents of
children with ASD also tended to be more vaccine hesitant compared with parents of children without ASD (28% vs. 10%, Fisher's
p = 0.14). Adjusting for age and child's gender, the odds of being vaccine hesitant were 4.0 (95% CI: 0.8, 20.5) times greater
among parents of children with ASD compared with parents of children without ASD. Additional results about attributions for
and beliefs about other causes of their children's delays are forthcoming.
Discussion: These results demonstrate the strength behind the theory of an autism-vaccine connection and reinforce the need
to understand how and when such beliefs emerge, particularly among families whose children receive an ASD diagnosis.
References/Citations:
• 1Goin-Kochel, R.P., Mire, S.S., & Dempsey, A.G. (2015). Emergence of autism spectrum disorder in children from simplex
families: Relations to parental perceptions of etiology. Journal of Autism and Developmental Disorders, 45, 1451-1463.