Children with Autism Spectrum Disorder Accessing Early Intervention in the Autism and Developmental Disabilities Monitoring (ADDM) Network

Background:  Evidence-based treatments provided by Part C early intervention services, hereafter referred to as “EI,” improve IQ, speech, and school performance for children with autism spectrum disorder (ASD). Best outcomes for these children are associated with early initiation of ASD-specific interventions.  In the U.S., early ASD identification has been linked to sex, race/ethnicity, developmental regression, and geographic location; however, little is known about characteristics of children with ASD receiving EI services. The CDC’s Early Autism and Developmental Disabilities Monitoring Network (Early ADDM) identifies ASD among 4-year-old children.  Two Early ADDM sites (New Jersey and Utah) collect information from EI, providing an opportunity to characterize children with ASD served by EI compared to those not.

Objectives: To describe the socioeconomic/demographic and diagnostic characteristics of children with ASD in two Early ADDM sites, comparing children who did and did not participate in EI services.

Methods:  In surveillance year 2010, NJ and UT Early ADDM sites identified 4-year-old children with ASD using validated population-based, multi-source record review methods. Characteristics of children with ASD served by EI were compared with children with ASD not served by EI using chi-square and t-tests.  Variables included sex, race/ethnicity, socioeconomic status (SES) indicators (parental ages and education duration at child’s birth), presence of co-occurring intellectual disability (ID), attention deficit with hyperactivity disorder (ADHD), or seizures, regression history, previous ASD diagnosis by a qualified professional, and age at first ASD evaluation.

Results:  NJ and UT Early ADDM sites identified 484 4-year-olds with ASD; 45% (N=218) participated in EI.  A greater proportion of parents of children served by EI were >34 years old and had >13 years of education as compared with parents of children not served by EI (Table 1). Although no significant differences in race/ethnicity were detected between the two groups, a smaller proportion of children served by EI were White, non-Hispanic (36%) than those not served by EI (47%).  No differences were detected in the frequency of co-occurring ID, ADHD, or seizures between children accessing and children not accessing EI. Children accessing EI were younger at first ASD evaluation (22.8 vs. 34.1 months, p<0.0001) and diagnosis (30.2 vs. 36.3 months, p<0.0001).  Children served in EI were significantly more likely to have a final case status of autism (p<0.001).  

Conclusions:  Study findings suggest a link between higher SES and EI use; however, there appears to be some indication that the role of race and ethnicity should be further explored. Children accessing EI were not more likely to acquire a community-based ASD diagnosis by age four; however, as expected, they were more likely to have an evaluation and diagnosis at a significantly younger age than children without documented EI access. Toddlers with earlier evaluations and diagnoses have more time to qualify for and participate in birth-to-three EI programs. Although not a perfect severity metric, the co-occurrence of ID, ADHD, or seizures was not associated with EI participation.  Additional exploration of the role of SES and other demographic factors in accessing universally-available EI programs for children with ASD is warranted.