One in 68 U.S. children was diagnosed with autism in 2010, a 30% increase over 2008 levels, according to a CDC report released Thursday.
In 2008, CDC found that one in every 88 children were diagnosed with autism.
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For the new report, CDC examined data from health and school records in 11 states, including Alabama, Arizona, Arkansas, Colorado, Georgia, Maryland, Missouri, New Jersey, North Carolina, Utah, and Wisconsin.
Researchers focused on children who were eight years old—the condition is most often diagnosed by that age—and looked to see which children met the criteria for having autism even if they had not yet been diagnosed. Researchers then calculated how common autism was in each state and overall.
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In addition to an increased rate of the disorder, the report found a rise in the amount of children who have higher IQs and also rank somewhere on the autism spectrum.
Further, autism rates remained higher among males, with one in 42 having the disorder, compared with females at one in 189, and white children. Officials said the racial disparity most likely is because of low reported rates among African-Americans and Hispanics.
The report also showed a wide variance in autism rates by state. For example, one in 175 children were diagnosed with the disorder in Alabama, while one in 45 were diagnosed in New Jersey. Overall, the report estimated that nearly 1.2 million U.S. residents under age 21 have autism.
While the report did not list a reason for the increase, experts believe the surge is because of higher diagnosis rates and awareness instead of an actual increase in children with the disease. Experts added that the increase was expected based on suggestions from other data (Bernstein, "To Your Health," Washington Post, 3/27; Stobbe, AP/Yahoo! News, 3/27; Weintraub, USA Today, 3/27).
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