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One in 50 US students has autism, study says

NEW YORK — A government survey of parents says 1 in 50 US schoolchildren has autism, surpassing another federal estimate for the disorder.

Health officials say the new number doesn’t mean autism is occurring more often. But it does suggest that doctors are diagnosing autism more frequently, especially in children with milder problems.

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The earlier government estimate of 1 in 88 comes from a study that many consider more rigorous. It looks at medical and school records instead of relying on parents.

For decades, autism meant kids with severe language, intellectual, and social impairments and unusual, repetitious behaviors. But the definition has gradually expanded and now includes milder, related conditions.

The new estimate released Wednesday by the Centers for Disease Control and Prevention would mean at least 1 million children have autism.

The new statistic comes from a phone survey of more than 95,000 parents in 2011 and 2012. Less than a quarter of the parents contacted agreed to answer questions, and it is likely that those with autistic kids were more interested than other parents , officials said.

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