Autism and Developmental Disabilities Monitoring (ADDM) Network

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The Autism and Developmental Disabilities Monitoring (ADDM) Network is a program funded by CDC to collect data to better understand the number and characteristics of children with autism spectrum disorder (ASD) and other developmental disabilities living in different areas of the United States.

ADDM Network goals are to:

  • Describe the population of children with ASD,
  • Compare how common ASD is in different areas of the country,
  • Measure progress in early ASD identification,
  • Identify changes in ASD occurrence over time, and
  • Understand the impact of ASD and related conditions in US communities.

ADDM Network fact sheet

What We’ve Learned

CDC estimates that about 1 in 44 8-year-old children have been identified with ASD (or 23.0 per 1,000 8-year-olds). These estimates from the ADDM Network are based on data collected from health and special education records of children living in 11 communities across the United States during 2018. Information was collected on children who were 8 years old because previous work has shown that, by this age, most children with ASD have been identified for services.

Learn more about autism prevalence estimates since the ADDM Network first began reporting in 2000.

Here are some other key findings from our most recent report about 8-year-old children:

  • The percentage of children identified with ASD varied widely among the 11 communities in this report, from 1.7% or 1 in 60 children in Missouri to 3.9%  or 1 in 26 children in California.
  • Boys were 4 times as likely to be identified with ASD as girls.
  • ASD occurs among all racial, ethnic, and socioeconomic groups. There was no overall difference in the number of Black, White, Hispanic, and Asian/Pacific Islander 8-year-old children identified with ASD. However, at several sites, the number of Hispanic children identified with ASD was lower compared to White or Black children.
  • Among children identified with ASD who had IQ scores available, about one-third (35.2%) also had intellectual disability.

Article: Prevalence of Autism Spectrum Disorder Among Children Aged 8 Years — Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2018

Key findings from the report about 4-year-old children:

  • Children born in 2014 were 50% more likely to receive an ASD diagnosis or ASD special education classification by 48 months compared to children born in 2010.
  • Among 4-year-old children, new patterns were found in the identification of ASD by race and median household income compared to previous ADDM Network data:
    • More Black, Hispanic, and Asian or Pacific Islander children were identified with ASD compared to White children; and
    • Children living in lower income neighborhoods had a higher rate of ASD identification compared to children living in higher income neighborhoods.

Article: Early Identification of Autism Spectrum Disorder Among Children Aged 4 Years – Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2018

Both reports are summarized in the 2021 Community Report from the Autism and Developmental Disabilities Monitoring Network.

Current ADDM Network Activities

  • In January 2019, CDC launched a 5thphase of funding for the ADDM Network (for tracking year 2018 and 2020).
  • Tracking of the number and characteristics of 8-year-old children with ASD has been ongoing since 2000.
  • Tracking among 4-year-old children began in 2010 to increase our understanding of the characteristics and early identification of younger children with ASD.
  • Follow-up of 16-year-olds began in 2018 and will help inform public health strategies to improve identification of and services for children with ASD. Tracking 16-year-old adolescents with ASD can also provide valuable information on transition planning in special education services and the planned trajectory for post-high school years.
  • In addition to tracking, sites also analyze the data to better understand ASD, and carry out education and outreach activities in their local communities.

Read about the work taking place at each site by clicking one of the following links:

ADDM Network Publications

To find ADDM publications related to ASD, visit our Autism Articles page. To find ADDM publications related to other developmental disabilities, including cerebral palsy, visit our Developmental Disabilities Articles page.