AsianScientist (May 10, 2011) – How prevalent is autism in children? The answer may be higher than previously thought.
The number of children diagnosed with autism and autism spectrum disorders (ASD) has increased dramatically since the 1980’s but it is not known if this is due to changes in diagnostic criteria or if actual prevalence has increased.
Information on childhood prevalence of autism and ASD is often inadequate because of variations in diagnostic criteria and because many epidemiological studies rely on case reports, an approach which misses undiagnosed cases.
In a first step towards answering this and other unresolved questions in autism research, an international team of investigators from South Korea, Canada, and the U.S. have completed the first comprehensive study of autism prevalence by surveying an entire population.
By studying all children (approximately 55,000) aged 7 to 12 in the Ilsan district of Goyang City in South Korea, the researchers came up with an estimate that about 1 in 38 South Korean children had ASD. This figure is almost three times higher than that reported in a 2006 study by the US Centers for Disease Control and Prevention. In that study, 1 in 110 children in the United States were estimated to have ASD, a figure that was considered to be surprisingly high at that time.
Does this mean that Koreans have higher rates of autism?
Experts think that this is unlikely, although cultural differences may affect diagnostic practice and prevalence estimates. Results from similar total population survey studies currently being conducted in India, South Africa, Mexico, and Taiwan may give us a more definitive answer in the near future.
A more likely interpretation is that autism and milder forms of ASD, such as Asperger’s syndrome, may be more common than previously thought and that, if researchers look carefully, especially in previously understudied, non-clinical populations, they may find more children with ASD.
Dr. Geraldine Dawson, the Chief Scientific Officer of Autism Speaks, the world’s largest autism science and advocacy organization which funded the study, said:
“These findings suggest that ASD is under-diagnosed and under-reported and that rigorous screening and comprehensive population studies may be necessary to produce accurate ASD prevalence estimates.”
Yale University psychiatrist Dr. Young Shin Kim, the lead investigator of the study which was published yesterday in the American Journal of Psychiatry, hopes that by identifying more children with ASD and describing the full spectrum of ASD clinical characteristics, children with ASD can benefit from early diagnosis and intervention for best outcomes.
Goyang City, the host of the Korean study, has responded to these findings by providing comprehensive assessment and intervention services for all first graders entering their school system. Dr. Kim hopes that others will follow Goyang City’s example so that any population based identification of children with ASD is accompanied by intervention services for those children and their families.
The article can be found at: Kim YS et al. (2011) Prevalence of Autism Spectrum Disorders in a Total Population Sample.
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Source: Autism Speaks.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.
