Changes in US Special Education Autism Eligibility Rates from 2010 to 2016

Background: Current U.S. estimates of the prevalence of autism spectrum disorders (ASD) are 1 in 59 (i.e., 170/10,000) children (Baio et al., 2018). Public schools provide necessary services for children with ASD; however, many children with a medical diagnosis of ASD do not have corresponding special education eligibility in ASD (Pinborough-Zimmerman et al., 2012; Rubenstein et al., 2018). Further, ASD identification rates vary across racial groups, with some evidence that African American children are identified at lower rates and older ages than Caucasian children (Baio et al., 2018; Locke et al., 2017).

Objectives: We evaluated changes in ASD special education eligibility rates in the U.S. between 2010 and 2016. Patterns of ASD eligibility rates in relation to eligibility rates for speech and language impairments (SLI) and developmental delays (DD) were considered, as well as patterns across age and race (i.e., Caucasian, African American).

Methods: Publicly accessible U.S. Department of Education special education data from the 2010-11 and 2016-17 school years were used with corresponding years of U.S. Census Bureau State Datasets. Data from 48 states, excluding Iowa (a non-categorical eligibility system) and Wyoming (missing data ), were analyzed. These analyses used overall numbers of children in special education and those with primary eligibilities in ASD, DD, or SLI.

Results: Between 2010 and 2016, the rate of ASD eligibility per 10,000 children increased from 40 to 56 for children ages 3 to 5, 81 to 105 for children 6 to 11, and 57 to 87 for children 12 to 18. The proportion of children eligible under ASD compared to all children eligible for special education increased between 1.7% and 3.3% across age ranges. Within the youngest age range (3-5 yrs) there was no correlation between ASD and DD rates (r = -0.08, p = 0.62) nor between ASD and SLI rates (r = 0.11, p = 0.47). The ratio of Caucasian to African American children ages 3 to 5 with eligibilities in the areas of ASD, DD, and SLI were 0.88 (M = 0.90, SD = 0.3), 0.87 (M = 0.91, SD = 0.3), and 1.42 (M = 1.77, SD = 1.1), respectively.

Conclusions: Special education ASD eligibility rates are one-third to two-thirds lower than ASD prevalence rates, though there is a trend toward greater identification between the years 2010 and 2016. Low rates of ASD eligibility rates for young children are consistent with past research but are troubling given the importance of early intervention (Baio et al., 2018; Zwaigenbaum et al., 2015). Given the lack of correlations between rates of ASD eligibility and rates of SLI and DD eligibility, we do not have evidence to suggest young children may be identified as having SLI or DD rather than ASD. However, differences in eligibilities were present across racial groups in young children. Specifically, Caucasian children were more likely to be identified with SLI, while African American children were more likely to be identified with ASD and DD, a finding which will be discussed in the context of literature.