Autism and Developmental Disabilities Monitoring (ADDM) Network

Photo: Child bouncing on large ball

The Autism and Developmental Disabilities Monitoring (ADDM) Network is a group of programs funded by CDC to estimate the number of children with autism spectrum disorder (ASD) and other developmental disabilities living in different areas of the United States. The ADDM Network sites all collect data using the same methods, which are modeled after CDC’s Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP).

ADDM Network goals are to:

  • Describe the population of children with ASD,
  • Compare how common ASD is in different areas of the country,
  • 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 59 children has been identified with ASD (or 16.8 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 2014. These 11 communities comprised 8% of the United States population of 8-year-olds in 2014. 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 2007.

Here are some other key findings from our most recent report:

  • The percentage of children identified with ASD varied widely among the 11 communities in this report, although five of them reported similar estimates of 1.3 percent to 1.4 percent. The highest prevalence estimate of 2.9 percent came from a community in New Jersey.
  • Boys were 4 times were more likely to be identified with ASD than girls.
  • While a higher percentage of white children were identified with autism compared to black children, and even more so compared to Hispanic children, these disparities were smaller when compared with estimates from previous years.
  • Among children identified with ASD who had IQ scores available, nearly a third (31%) also had intellectual disability.
  • About 42% of children identified with ASD were evaluated for developmental concerns by age 3 years. This percentage is lower than the goal set by Healthy People 2020 that 47% of children with ASD have a first evaluation by age 3 years.
  • Even though ASD can be diagnosed as early as age 2 years, most children were not diagnosed with ASD by a community provider until after age 4 years.
  • Recent changes in the clinical definition of autism had little impact on the percentage of school-aged children identified as having ASD.

Article: Prevalence of Autism Spectrum Disorder Among Children Aged 8 Years — Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2014
Community Report: 
2018 Community Report from the Autism and Developmental Disabilities Monitoring Network

Current ADDM Network Activities

  • In January 2019, CDC launched a 5th phase of funding for the ADDM Network (for tracking year 2018). However, ADDM Network sites previously funded in January 2015 continue work on tracking year 2016. These data will be published in 2020. See the table below for a comparison between the two tracking years.
Current ADDM Network Activities for 2016 and 2019
Tracking Year 2016 Tracking Year 2018
Date funded January 2015 January 2019
No. of sites funded 10

(plus MADDSP,
the ADDM Network site
administered by CDC)


(plus MADDSP)

No. of sites tracking 4-year-olds 6 11
No. of sites tracking 8-year-olds 11 11
No. of sites following up 16-year-olds N/A 4
  • Tracking among 4-year-old children increases our understanding of the characteristics and early identification of younger children with ASD.
  • Follow-up of 16-year-olds is a new activity for the ADDM Network, 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.
  • Some ADDM Network sites also track the prevalence of other developmental disabilities, including cerebral palsy and intellectual disability.
  • In addition to tracking, sites also conduct analyses of the data to better understand changes over time in the number of children identified with 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.