Dr. Shattuck has a paper that states the opposite.

Also, if you want to argue from CDDS data, that is a different dataset entirely. In the CDDS data, it is very clear that the number in the MR category has gone down markedly as autism has gone up.

You may want to stick to what she says, rather than her “bona fides”.

Dr. Healy was a member of TAASC, an organization paid by Tobacco company interests to deny the dangers of second hand tobacco smoke.

They also denied global warming, but, as a medical doctor, that may not be Dr. Healy’s domain at TAASC.

Dr. Healy actually says very little. Much of what she said in the past was incorrect (such as her assertions against the IOM).

Odd, he says it quite clearly in his patent.

“it is estimated that 26.4% (95% CI 16.25–36.48) of the increased autism caseload in California is uniquely associated with diagnostic change through a single pathway—individuals previously diagnosed with MR.”

Taken together with the results of the UC Davis / MIND study which Joseph mentioned above this would seem to seriously undermine attempts to use the Californian data to support the idea of an autism epidemic.

Joseph, the Cal study did not find that a change in diagnosis was the only related factor in the increase in incidence.

I assume you’re referring to the UC Davis / MIND study. That study did not really quantify “change of diagnosis” (diagnostic substitution) at all. It only looked at age at diagnosis, changes in criteria, and inclusion of “milder” cases. It finds that these factors might explain a 4.26-fold increase in CalDDS, whereas they expected to explain a 6.85-fold rise. It’s not clear why they think this difference is statistically significant. The paper doesn’t say.

The paper admits they did not account for certain factors that ought to be significant, such as awareness. Hence the paper’s tempered conclusion.

The paper had many very serious problems. I listed them at the end of this post:

http://autismnaturalvariation.blogspot.com/2009/01/age-of-diagnosis-analysis-is-also-wrong.html

BTW, it’s not as easy to quantify diagnostic substitution in the CalDDS database, as it would be in IDEA. That’s simply because in IDEA there’s a “primary disability” category, whereas in CalDDS a “client” has multiple categories simultaneously. So you shouldn’t expect there to be a decrease in mental retardation classifications, for example, as they are based on assessments of IQ.

The number of of young people diagnosed with austism has most certainly risen and I’ve shared data to support this. The rate incidence of other special ed categories has been steady while autism rates have increased.

Feel free to share some supporting evidence for your position.