As autism diagnoses rose, intellectual disability diagnoses fell, reports a Penn State study on “diagnostic substitution.” Many of the “new” autism cases reflect changes in how children are labeled rather than a rise in kids with learning or communications problems, researchers concluded.
Autism prevalence rates rose from 1 in 150 children in 2000 to 1 in 68 children in 2010, according to a Centers for Disease Control report, reports Ed Week‘s Christina Samuels.
The fastest-growing group of children with autism spectrum disorder are those with normal to above-average intelligence, said the CDC’s Jon Baio. It’s not likely these children would have been identified as having an intellectual disability, he said. “What has changed to put children today at an increased risk of having autism? We really don’t know.”
The CDC’s figures, which aren’t based on examination of children, may be unreliable, says David Mandell, associate director of the Center for Autism Research at The Children’s Hospital of Philadelphia.