What is Autism Spectrum Disorder (ASD)?
Autism spectrum disorders (ASD) are developmental disorders that affect individuals linguistically, behaviorally, and socially. This is called a “spectrum” disorder because different individuals are affected differently and to varying degrees. Determining ASD can be difficult because there is no accurate medical test. Some people are not diagnosed until puberty or adulthood.
For this study, researchers looked at data from the New Jersey Autism Study (NJAS) from 2000 to 2016. They identified 4,661 of her 8-year-olds with her ASD in He four counties in New Jersey (Essex, Hudson, Ocean and Union).
Autism does not necessarily overlap with intellectual disability
Of those diagnosed with autism, 1,505 (32.3%) had an intellectual disability and 2,764 (59.3%) did not. The team also found that the rate of autistic children with intellectual disabilities increased 200% over 16 years, from 2.9 per 1,000 to 7.3 per 1,000. In contrast, the rate of ASD without intellectual disability jumped from 3.8 per 1,000 to 18.9 per 1,000 to 500%.
The study points to a growing body of research suggesting that autism does not necessarily overlap with intellectual disability.
“One assumption about ASD is that it occurs with intellectual disability,” said Josephine Shenoda, adjunct professor at the Rutgers School of Public Health and lead author of a study published today in the journal Pediatrics. “This claim is supported by older studies suggesting that up to 75% of children with autism also have intellectual disabilities.”
“Our paper shows that this assumption is not true. In fact, two out of three children with autism in this study had no intellectual disability at all.” says Professor Shenouda.
