The Centers for Disease Control and Prevention is reporting for the first time on its efforts to expand tracking of children with autism to include teens on the spectrum.

The federal agency has long studied autism among 8-year-olds in various locations across the nation. The surveillance data is relied on to provide an estimate of the number of children believed to have the developmental disability. More recently, the CDC started collecting data on 4-year-olds as well.

Now, in a study published in the Journal of Adolescent Health, the agency is providing a look at individuals with autism who were age 16 in 2018.

For the report, sites in Arkansas, Georgia, Maryland, Utah and Wisconsin that are part of the CDC’s Autism and Developmental Disabilities Monitoring Network reviewed records to determine how 16-year-olds who previously were identified by the network as 8-year-olds in 2010 have fared.

Notably, more than half of teens with autism also had a diagnosis of attention-deficit hyperactivity disorder or anxiety. And, nearly 17% had “indications of suicidal behavior/ideation,” the study found.

In a significant number of cases — 14.7% — an autism diagnosis was initially ruled out before being assigned, the findings show, and more than 1 in 10 children with autism were not identified until after age 8. These kids were more likely to be Hispanic, verbal, born at low birth weight, have high IQ or adaptive scores and have co-occurring neuropsychological conditions.

The researchers found that a plan was in place for nearly all of the teens with autism to help them transition to adulthood, but they noted that more could be done given that over 30% of these plans lacked a goal related to postsecondary living arrangements, daily living skills and community participation.

“In this first ADDM Network report on children aged 16 years with ASD, we identified factors associated with ASD identification after age 8 years that may be useful to providers when screening and diagnosing ASD to ensure that children are identified and receive services as early as possible,” the researchers wrote in their findings.

The information on teens is part of a broad effort by the CDC to track the experiences of children with autism as they grow. The agency’s most recent report on 8-year-olds found that prevalence of the developmental disability has increased to 1 in 36 children.

The CDC plans to issue additional findings on the group of 16-year-olds in the latest study with specific details on special education services and transition planning, according to Michelle Hughes, an epidemiologist at the CDC’s National Center on Birth Defects and Developmental Disabilities who led the study on teens. A report is also expected on those who were age 16 in 2020.

Future data collection on 16-year-olds will be more similar to the CDC’s surveillance of children at ages 4 and 8, Hughes said. In addition, she indicated that the agency is piloting an effort to collect information about those with autism in young adulthood in order to assess how they are influenced by what happens in high school.