An increasing number of American children have developmental disabilities, the federal government says, even as autism and intellectual disability rates remain largely steady.

Between 2014 and 2016, the prevalence of developmental disabilities among kids ages 3 to 17 increased from 5.76 percent to 6.99 percent, according to figures released Wednesday from the U.S. Centers for Disease Control and Prevention.

The rise stems from an uptick in children diagnosed with a developmental delay other than autism or intellectual disability, the federal agency said.

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The findings come from data collected through the National Health Interview Survey, a routine in-person government poll soliciting information about all types of health matters from people across the country.

As part of the inquiry, parents were asked if they had ever been told by a doctor or health professional that their child had intellectual disability, autism or any other developmental delay.

Reported rates of autism and intellectual disability remained relatively stable, the report found, even as the overall incidence of developmental disabilities climbed.

Across all conditions, the CDC found that prevalence was “significantly higher” among boys than girls. The diagnoses were least common among Hispanic children compared to other racial or ethnic groups.

“Prevalence among age groups varied by condition, which may reflect recent improvements in awareness and screening for developmental delay, resulting in younger cohorts having a higher diagnosed prevalence,” wrote Benjamin Zablotsky, Lindsey I. Black and Stephen J. Blumberg from the CDC’s National Center for Health Statistics.

The rate of developmental disabilities reflected in the report is lower than in some previous findings from the same survey, the CDC noted. But the agency said that current findings are based on a more restrictive definition of developmental disabilities — excluding conditions like attention deficit hyperactivity disorder and learning disabilities — than has been used at times in the past.