(NEW YORK) -- Many children may be diagnosed with autism years too late to benefit from early behavioral intervention, according to 2011 national survey findings released Thursday from the National Institute of Mental Health.
Intensive behavioral therapy for autism, which can begin as early as age two, can significantly improve language and thinking skills in children with autism, according to the National Institutes of Health. The therapy, which helps develop a child's social and behavior skills within different environments, is considered among the best forms of treatment by the American Academy of Pediatrics.
However, the survey found that more than half of the children had reached age five before they were first identified as having an autism spectrum disorder.
Although children can continue to benefit from behavioral interventions after age five, earlier behavioral intervention is associated with better outcomes, according to many experts.
"It is critical that we address the barriers that are preventing children from receiving early intervention," said Geraldine Dawson, chief science officer of Autism Speaks, who was not involved in the study.
More than 1,400 children ages 6 to 17 with autism were included in the survey. The survey looked at diagnosis of the disorder within the last 17 years.
The older children may have been receiving some sort of medical assessment for their condition before receiving a formal diagnosis, according to Lisa Colpe, chief officer of clinical and population epidemiology research at the National Institute of Mental Health's and co-author of the study.
"It's still a very complex disorder to diagnose and does take some time," said Colpe. "These ages mean that they have been getting assessed for some period of time before getting a diagnosed."
Ninety percent of the children diagnosed participated in some form of developmental service including occupational therapy, speech and language therapy, and social skills training, according to the study. However, fewer than half of the children underwent behavioral therapy.
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