Figures just out from the U.S. government suggest there's been an explosion in autism cases in the past few years.
It all depends who you ask.
The numbers themselves aren't in dispute. They come from the Centers for Disease Control and Prevention, which has been monitoring the prevalence of autism among 8-year-olds at sites around the nation since 2000.
The latest statistics, from 2006, show that 1 in 110 children in these sites had autism or a related disorder. That's a 57 percent increase over the comparable figure from 2002.
The findings are pretty close to another recent estimate that found 1 in 100 kids had autism spectrum disorders.
Advocacy groups say the latest CDC report confirms the existence of an "autism epidemic."
"For the first time, we are hearing our government acknowledge the real increase in autism," said Autism Society President Lee Grossman in a statement emailed to reporters.
The Autism Speaks Web site labeled the increase "staggering" and called for an immediate increase in federal funding to address the "growing national autism public health crisis."
"The increase in autism points to environmental factors as the primary cause of autism," said a statement from Sallie Bernard, Executive Director of SafeMinds, a group that sees a link between autism and mercury in childhood vaccines.
But Catherine Rice of the CDC and other researchers who analyzed the data were considerably more cautious about interpreting the results.
Their paper notes that it's still not clear whether the change represents a "true increase" in prevalence or just better identification of children with disorders related to autism.
One reason for their caution is the wide variations in autism prevalence they found. For example, the 2006 data showed that the prevalence was three times higher in Missouri than in Florida.
It's highly unlikely that means kids in Missouri are really three times as likely to have an autism-spectrum disorder. A more likely explanation is that regional differences in how children are identified can produce wildly different results.
Rice and her co-authors also note that community awareness, earlier detection and better school and health records can all have a big effect on the apparent number of children with autism.
As a result, the CDC is still not ready to declare an "autism epidemic." The CDC's Rice held a press briefing on the findings. A transcript of the session will be available on the CDC's Web newsroom, the agency said.