By MIKE STOBBE
AP Medical Writer
NEW YORK (AP) – The government estimates that autism becomes more common, but it's only a small increase and some experts think it's mostly explained by better diagnosis of it Becoming a minority child
About 1 in 59 US children were referred to as autism in 2014, according to a report from the Centers for Disease Control and Prevention, which focused on 8-year-olds. That's from 1 in 68 children in 2010 and 2012.
White children are more commonly diagnosed with autism than black or Hispanic children, but the gap has closed dramatically. Autism used to be 20 percent higher in white children than black children, and this difference shrank to 1
This increased recognition in minority children is likely a major reason for the overall increase, CDC researchers said.
The causes of autism are not well understood and it is not clear if other factors could also play a role – such as more couples having babies later in life, said Thomas Frazier, Head of Advocacy Research Organization Autism Speaks.
"There is still a lot to do to better understand why this is happening," Frazier said about the rise.
There are no blood or biological tests for autism. It is identified by judgments about the behavior of a child. Traditionally, autism has been diagnosed only in children with severe language and social impairments and unusual, repetitive behaviors. But the definition gradually expanded, and autism is now an abbreviation for a group of milder, related conditions.
The new CDC report is based on a tracking system in 11 states focusing on 8-year-olds because most cases are diagnosed at this age. Researchers are reviewing health and school records to see which children fulfill criteria for autism, even if they have not been formally diagnosed. It is one of three CDM autism estimates, but is considered the most stringent.
"It's the gold standard," said Alison Singer, president of the Autism Science Foundation, an autism advocacy and philanthropy organization.
The researchers collected data from Arizona, Arkansas, Colorado, Georgia, Maryland, Minnesota, Missouri New Jersey, North Carolina, Tennessee and Wisconsin, spending a network of about 300,000 children. The 1 in 59 was an average: It was as high as 1 in 34 in New Jersey and as low as about 1 in 75 in five states.
Why the difference? Researchers say rates tend to be higher in states where they can access more records.
For years the estimate jumped, though it was not clear why. A report published in 2007 put the estimate at 1 in 150, or the equivalent of about a child in 5 or 6 classrooms. The new 1-in-59 number equals 1.7 percent.
Heather Cody Hazlett, a psychologist at the University of North Carolina, described the slight increase from 2012 to 2014 as unsurprising.
It explores new ways to recognize autism earlier. It is discouraging that less than half of all autistic children are diagnosed when they are 4 years old.
There is still a time delay between the first illness of the parents and the diagnosis of children. Many doctors may be reluctant to jump to an autism diagnosis on a younger child because they "try to be cautious and not alarming," Hazlett said.
But this may delay therapy or other services.  Deborah Christensen of the CDC, one of the authors of the study, said, "We need to do more to make sure children with developmental concerns are evaluated quickly."
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