An autism study in South Korea suggests that many children worldwide are going undiagnosed.
The study by the Yale Child Study Center found that one in every 38 children showed some signs of autism, much higher than the rate in the United States of one in every 100 children.
Researchers say instead of basing the study on education and medical records like the U.S. study, the South Korean study cast a wider net. It questioned the parents of 55,000 mainstream children ages seven to 12 in a city near Seoul. About 63 percent of parents participated.
Researchers say two-thirds of the children were found to have autism traits that had never been diagnosed, and most of those symptoms were very mild. Other experts not connected to the study say it's not even clear whether all these children would need special services.
The study is in Monday's issue of the "American Journal of Psychiatry."
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