The Centers for Disease Control and Prevention reports that the prevalence of the autism spectrum disorder among 8-year-olds increased 30 percent from 2008 to 2010. The rate of ASD has gone from 1 in 88 to 1 in 68. The CDC’s report is based on a review of records—from psychiatrists, schools, pediatricians, physical therapists, neurologists, and psychologists—from 11 different geographic regions in the U.S. There is huge variation between those regions. One in 175 children was diagnosed with the disorder in Alabama, compared to 1 in 45 in New Jersey. There is also a huge variation in race, as white children were far more likely to be identified as on the spectrum than black or Hispanic children.
To the lay parent, this sounds both confusing (are more kids in New Jersey really autistic?) and alarming (1 in 68?!). So I asked Dr. Catherine Lord, the founding director of the Center for Autism and the Developing Brain at New York-Presbyterian Hospital, to help me parse the stats.
For this report, the CDC looked at kids who have been given a diagnosis on the autism spectrum but also at kids whose reported symptoms fit the criteria for ASD but have not been officially diagnosed—the idea being that the CDC would catch the kids who were falling through the cracks. But the CDC didn’t find more kids in states like Alabama and Colorado who fit the criteria but weren’t already diagnosed than it did in Maryland or Jersey, where rates of autism are higher. Lord doesn’t believe that kids in New Jersey just naturally have four times the rate of autism that kids in Alabama do, so the numbers suggest to her that kids in the states with lower numbers “are not being referred for a diagnosis, or the [experts] are not giving good enough notes.”
The same goes for racial disparities. Lord says, “The notion that there are such discrepancies [in diagnosis] is disturbing. Something’s not right.” The CDC agrees, and notes in the report’s conclusion that they are working to account for the racial and geographic discrepancies.
As for the overall rise, we can’t know whether there are more autistic children now than there were in previous generations, because we’re so much more aware of the disorder today than we’ve ever been. (Lord does not believe that autism is being overdiagnosed.) The criteria for autism didn’t change between 2008 and 2010 (though the criteria did change in 2013), and a 30 percent rise does seem like a lot to simply attribute to raised awareness.
Still, there is no indication that there’s a rise in severity. Just as they did in 2008, the numbers refer to everyone on the spectrum, which includes a huge range, from extremely mild to extremely severe. In 2008, 62 percent of children with ASD did not have an intellectual disability (which means an IQ over 70). In 2010, 69 percent of children did not have an intellectual disability. Lord compares the breadth of this study to one about people with sight problems, which included “both people who have to wear glasses when they’re 60 to read up close, up to people who are functionally blind. It is a very, very broad range.”
Some of the kids on the spectrum are socially awkward but doing OK, and others need more help. Which is why Lord frames the fact that the numbers are going up—even as much as 30 percent—as something benign, not frightening. To her, it means more people are getting diagnosed, and the diagnosis can be a first step toward getting kids whatever help they might need.