We are all aware there is a concern that the prevalence of autism spectrum disorder (ASD) is increasing, but how valid is this perception? Unfortunately, this is a difficult question to answer since there is no national registry of diagnosed cases. One way to find out the prevalence is to ask parents. Kogan et al. (10.1542/peds.2017-4161) report on in an analysis of the 2016 National Survey of Children’s Health (NSCH), a nationally representative survey of over 50,000 children ages 0-17 years. Parents were asked whether their children had been given the diagnosis of ASD by a clinician, whether their child or children currently have a ASD, and if yes, how they are treating it. The authors estimate a point prevalence of 1.5 million children ages 3-17 have ASD based on a parent report. This would mean 1 in 40 or 2.5% of US children have ASD. The study also provides insight into the barriers families of children with ASD have in accessing the care their children need, as well as the types of treatments these children are receiving.
So does this mean that this prevalence rate is uniform across the country? Not necessarily, according to an accompanying commentary (10.1542/peds.2018-2950) by Drs. Broder-Fingert, Sheldrick, and Silverstein from Boston Medical Center and Tufts, all with expertise working with children with ASD. The authors point out that there is significant heterogeneity among states in ASD prevalence estimates, and a single national number fails to show the variances by state that currently exist. They argue that while a national rate does not tell the whole story, which includes significant differences in how children with ASD are diagnosed and how services for these children are accessed. Unfortunately, the NSCH sample of 50,000+ does not allow state by state analysis because the number of subjects is not sufficient. Both the study and commentary are essential reading if you provide care for children with ASD, and based on the prevalence rates described nationally in the study or by state, in the commentary, you most likely do.