Autism spectrum disorder, or ASD, comprises a range of neurodevelopmental disorders, often marked by communication difficulties, and restricted or repetitive behaviors, among other symptoms. The higher estimate of affected children may be the result of better understanding of the disorder and better reporting.
“In the past we thought of [autistic] children as being severely affected, meaning children with intellectual disabilities,” explained Dr. Marshalyn Yeargin-Allsopp, chief of CDC's developmental disabilities branch. “We recognize now that autism is a spectrum. Our understanding has evolved to the point that we understand that there are children with higher IQs and children who perhaps are even not receiving special education services [who have the condition].”
Significant gender, race and regional differences also were noted in the findings.
The condition was found to be nearly five times more common in boys, of whom 1 in every 42 had an ASD diagnosis, compared to 1 in every 189 girls. White children are more likely to have ASD than black or Hispanic children. In Alabama, only 1 in 175 children had autism spectrum disorders, compared with 1 in every 45 children in New Jersey.
The reasons for the disparities remain unclear, but CDC experts suggested that in areas where ASD prevalence was lower, access to community resources for identifying, diagnosing and serving children with the disorder may also have been low.
Currently, no medical test—such as a blood test—can determine whether a child has autism, making the condition difficult to diagnose. The most common diagnostic approach includes a short screening test of basic learning skills, followed by a comprehensive diagnostic evaluation, which may include hearing and vision screenings, as well as genetic and neurological testing. There also is no cure for the disorder, but experts say there are ways to minimize symptoms and they encourage early detection.
“Early identification is the most powerful tool we have right now,” said Coleen Boyle, director of CDC's National Center on Birth Defects and Developmental Disabilities. “Health professionals, educators and child care providers should use these data to ensure children with ASD are identified as early as possible and connected to the services they need.”
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