The first national survey of autism in the United States found 300,000 American children have been diagnosed with autism.
The Centers for Disease Control released the data Thursday, The Washington Post reported. The CDC said the diagnosis is four times more common in boys than girls.
The highest rate of reported autism is in affluent white families, something researchers say probably reflects access to medical care and not the actual incidence of the condition.
Individuals with autism spectrum disorders have difficulty in social interactions and communication with others. The pattern of behavior varies widely.
"It's not like leukemia or a broken bone where a diagnosis will be made no matter what your social class is," said Gary Goldstein, head of the Kennedy Krieger Institute at Johns Hopkins University. "You have to be an advocate."
The number of diagnosed cases grew quickly in the 1990s, which most experts believe was the result of more public awareness.
Copyright 2006 by United Press International
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