Study finds more than 2% of children have autism

A new survey has found a big jump in the number of children with autism, although researchers caution that the increase is likely due to the way that questions were asked.

More than 2.2% of children ages 3 to 17 — about one in 45 — have autism, according to the Center for Disease Control and Prevention's National Health Interview Survey, conducted in 2014. The annual survey found autism rates of 1.25%, or one in 80 people, from 2011 to 2013.

People with autism — a complex condition of brain development — tend to have difficulty with social interaction and verbal and nonverbal communications and are prone to repetitive behaviors. While the CDC report describes autism as a development disability, some people with autism say they are simply different, rather than disabled.

The dramatic increase in autism rates in the latest survey suggests that parents used different labels to describe their children than in earlier years, said Katherine Walton, an assistant professor of psychiatry and psychology at Ohio State University, who wasn't involved in the new study.

While the number of children diagnosed with autism went up, the number reporting children diagnosed with "other development delays" went down. Yet the overall number of parents who reported any developmental disability in their kids — about 5.75% — remained the same.

Parents may have changed the way they labeled their children because of changes made to the way that researchers interviewed them, said study coauthor Benjamin Zablotsky, a researcher at the CDC's National Center for Health Statistics.

Different surveys have produced varying autism rates.

The new survey results are similar to those of one released in 2013, which found 2% of children had autism. A study released in 2014 found the autism rate closer to 1.5%.

Although studies have found rising rates of autism for two decades, there is no clear explanation why. It's possible that more children are developing the condition, Walton said. But she notes that the definition of autism is much broader today than it was decades ago. People also are more aware of autism, leading to increased testing of younger children. Multiple studies have ruled out vaccines as a cause of autism.

Alison Singer, whose daughter has autism, said she's less interested in estimating the prevalence of autism than in securing support and services for her child.

"As parents, we're not interested in '1 in 80' or '1 in 100.' We're interested in our one," said Singer, president of the Autism Science Foundation. "We're interested in getting access to services, making sure that children are in the appropriate classrooms and that adults with autism receive supported housing and employment, and that we're funding research to find the cause."