About 0.7% of U.S. children may suffer from an “autism spectrum disorder.”

Researchers at the U.S. Centers for Disease Control and Prevention have publicized that finding in a summary of research on the disorders conducted by a team of outside researchers.

The researchers looked at 8-year-old children in 6 U.S. communities in 2000 and 14 U.S. communities in 2002.

The researchers found that 0.67% of the children studied in 2000 and 0.66% of the children studied in 2002 had autistic spectrum disorders, officials report.

The scientists included autistic disorder, pervasive developmental disorder – not otherwise specified and Asperger syndrome in their study.

In the past, researchers have estimated that about 0.05% of children had autism, officials report.

Officials note that it is not clear whether the high rate of ASDs detected in the 2000 and 2002 studies was due to an increase in the prevalence of ASDs or a change in definitions.