ATLANTA -- About 1 in 150 American children has autism, an urgent public health concern, said US health officials yesterday who reported on the largest study done so far on the disorder.
The new numbers, based on 2002 data from 14 states, are higher than previously reported.
Advocates said the study provides a new understanding of how common autism is, and should fuel efforts to get the government to spend hundreds of millions of dollars more on research and services.
"This data today shows we're going to need more early-intervention services and more therapists, and we're going to need federal and state legislators to stand up for these families," said Alison Singer, spokeswoman for Autism Speaks, the nation's largest organization advocating more services for autistic children.
The study by the US Centers for Disease Control and Prevention calculated an average autism rate of 6.6 per 1,000.
That compares with last year's estimated rate of 5.5 per 1,000.
The research involved a review of medical and school records for children in 14 states and gives the clearest picture yet of how common autism is in some parts of the country, CDC officials said.
Those states, however, are not demographically representative of the nation as a whole, so officials cautioned against using the results as a national average.
The data came from Alabama, Arizona, Arkansas, Colorado, Georgia, Maryland, Missouri, New Jersey, North Carolina, Pennsylvania, South Carolina, Utah, West Virginia, and Wisconsin.
The study does not indicate whether autism is increasing -- a controversial topic, driven in part by the contention by some parents and advocates that autism is linked to a vaccine preservative. The best scientific studies have not borne out that claim.
"We can't make conclusions about trends yet" because the study's database is too new, said Catherine Rice, a CDC behavioral scientist and the study's lead author.
Autism is a complex disorder usually not diagnosed in children until after age 3. It is characterized by a range of behaviors, including difficulty in expressing needs and inability to socialize. The cause is not known.