The Centers for Disease Control and Prevention estimates that 1 in 68 children (or 14.7 per 1,000 eight-year-olds) in multiple communities in the United States has been identified with autism spectrum disorder (ASD). This new estimate is roughly 30 percent higher than previous estimates reported in 2012 of 1 in 88 children (11.3 per 1,000 eight year olds) being identified with an autism spectrum disorder. The number of children identified with ASD ranged from 1 in 175 children in Alabama to 1 in 45 children in New Jersey.
This is the sixth survey reported from the CDC’s Autism and Developmental Disabilities Monitoring (ADDM) Network, an active surveillance system set up in 2000. In 2010, it gathered medical and school records for eight year olds from 11 ADDM sites in the United States. Surveillance is conducted in two phases. The first consists of screening evaluations performed by professional providers in the pediatric health clinics, specialized programs, and public schools. In the second phase, records are reviewed by trained clinicians to determine ASD case status. A child meets case definition for ASD if a comprehensive evaluation ofhat child is consistent with the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) autistic disorder, pervasive developmental disorder–not otherwise specified (including atypical autism), or Asperger disorder.
The upward trend in prevalence is consistent with recent studies conducted in the US and Canada. It can be attributed in large part to a combination of better detection methods, increased training of medical professionals, diagnostic subsition, and greater public awareness of the disorder.
Only 80% of all children identified as autistic had previous eligibility for autism special education services, or a DSM-IV diagnosis. That percentage is nearly the same as for the last two ADDM surveys, which indicates a large population of autistic children who are either undiagnosed or misdiagnosed.