The Centers for Disease Control released a new survey today finding that one in 68 children in the US has autism, up from one in 88, which the agency reported two years ago. The new prevalence figure, which is based on a sample of 8-year-olds taken in 2010, is a 29 percent increase over the figure for 2008, and a 123 percent increase in the figure for 2002.
• Gender differences: The new figure breaks down into one in 42 boys and one in 198 girls. That ratio has remained constant, though it varies among individual states.
• Ethnic differences: Non-Hispanic white kids were almost 30 percent more likely to be diagnosed than non-Hispanic black children, and 50 percent more likely than Hispanic children.
• Intellectual disability: The number of children diagnosed with autism who do not have intellectual disability has risen to 46 percent, up from 32 percent in 2002.
• Age of diagnosis: The median age of the first diagnosis is 4.5 years, not significantly different from the last survey.
• State breakdown: Prevalence of autism diagnoses varies a great deal among states in the survey—from 5.7 to 21.9 per 1,000 children. The lowest rate is Alabama and the highest is New Jersey.
The survey is based on a sample of kids in 11 sites around the country who have been identified by records from medical providers or school services as having an autism diagnosis. Records are then scrutinized by professionals to check them against accepted diagnostic criteria for autism.
Since it’s based on the 2010 survey year, this survey reflects diagnostic criteria for autism-related diagnoses from the DSM-IV-TR, rather than the new criteria in DSM-5 that was released in 2013. Included in the prevalence figures are all children diagnosed with autism, PDD-NOS, and Asperger’s Syndrome, which have all been combined more recently into ASD.
The CDC reports that the distribution of children among these subtypes has not changed significantly since 2006.