Prevalence and Disparities in the Detection of Autism Without Intellectual Disability.

This study looked at over 4,600 children with autism in New York and New Jersey over 16 years. They found that 1 in 3 autistic children also had intellectual disability. The number of autistic children without intellectual disability increased much faster than those with it. However, Black and Hispanic children, as well as those from less wealthy areas, were less likely to be diagnosed with autism when they didn't have intellectual disability, showing important inequalities in diagnosis.

This cross-sectional surveillance study analyzed 4,661 8-year-olds with autism spectrum disorder in the New York-New Jersey Metropolitan Area from 2000-2016. The study found that 32.3% had co-occurring intellectual disability (ASD-I) while 59.3% did not (ASD-N). Over the 16-year period, ASD-I prevalence increased 2-fold while ASD-N increased 5-fold. Significant disparities emerged: Black children were 30% less likely to be identified with ASD-N compared to white children, and children in affluent areas were 80% more likely to be identified with ASD-N than those in underserved areas.

Males showed higher prevalence regardless of intellectual disability status, though male-to-female ratios were slightly lower in ASD-I cases.

Findings highlight critical diagnostic disparities requiring targeted interventions for minority and underserved communities. The high proportion of ASD cases without intellectual disability suggests need for enhanced screening tools and training for higher-functioning presentations. Results inform resource allocation and service planning decisions.

Cross-sectional design prevents determination of causality. Study limited to one metropolitan area, potentially limiting generalizability. No information provided about diagnostic methods or validation procedures. Abstract does not specify exact sample size or response rates.

Intellectual ability predicts functional outcomes for children with autism spectrum disorder (ASD). It is essential to classify ASD children with and without intellectual disability (ID) to aid etiological research, provide services, and inform evidence-based educational and health planning. Using a cross-sectional study design, data from 2000 to 2016 active ASD surveillance among 8-year-olds residing in the New York-New Jersey Metropolitan Area were analyzed to determine ASD prevalence with and without ID. Multivariable Poisson regression models were used to identify trends for ASD with ID (ASD-I) and without ID (ASD-N).

Overall, 4661 8-year-olds were identified with ASD. Those that were ASI-I were 1505 (32.3%) and 2764 (59.3%) were ASD-N. Males were 3794 (81.4%), 946 (20.3%) were non-Hispanic Black (Black), 1230 (26.4%) were Hispanic, and 2114 (45.4%) were non-Hispanic white (white). We observed 2-fold and 5-fold increases in the prevalence of ASD-I and ASD-N, respectively, from 2000-2016.

Black children were 30% less likely to be identified with ASD-N compared with white children. Children residing in affluent areas were 80% more likely to be identified with ASD-N compared with children in underserved areas. A greater proportion of children with ASD-I resided in vulnerable areas compared with children with ASD-N. Males had higher prevalence compared with females regardless of ID status; however, male-to-female ratios were slightly lower among ASD-I compared with ASD-N cases.

One-in-3 children with ASD had ID. Disparities in the identification of ASD without ID were observed among Black and Hispanic children as well as among children residing in underserved areas.