Comments on: It Doesn’t Look Like It’s Declining

By: In 1931… : Left Brain/Right Brain

In 1931… : Left Brain/Right Brain — Thu, 27 Sep 2007 02:46:53 +0000

[...] It Doesn’t Look Like It’s Declining [...]

By: Joseph

Joseph — Sun, 23 Sep 2007 13:58:54 +0000

To elaborate on that point, suppose the 3-5 caseload of autistics in CDDS grows to a level where it includes 2% of the 3-5 population of children in the state. Obviously, that wouldn’t be something that can be brushed off by saying “nah, that’s not epidemiological data”, unless one could show, for example, that most kids classified with ASD in the system are actually ADHD or something.

But the numbers in CDDS have traditionally been low, so any gradual and smooth caseload increase can easily be explained as recognition catching up with the epidemiology.

The current 3-5 CDDS prevalence of autism is roughly 40 in 10,000.

By: Schwartz

Schwartz — Sun, 23 Sep 2007 00:28:27 +0000

“The California DDS provides a wealth of information that is by no means useless. However, itâ€™s important to understand the caveats of the data. ”

OK, I’m glad someone thinks so, and I agree it can at least provide a lower bound.

I’m just so used to people explaining six different ways that the CDDS data is useless for any analytics regarding the rates of Autism—usually in response to Kirby.

By: A Non

A Non — Sun, 23 Sep 2007 00:26:37 +0000

The real decline is among 2.5 year old Aquarians with blue eyes. Check it out David.

By: Sullivan

Sullivan — Sat, 22 Sep 2007 23:11:28 +0000

My guess on reading the “statistically significant” comment from Mr. Kirby was that it was probably from an email.

“Dear David. Take a look, the numbers went down. I checkd and it is statistically significant. Sincerely, EOHarm member 1023”

By: isles

isles — Sat, 22 Sep 2007 16:00:03 +0000

“But itâ€™s possible David Kirby is using a different method to calculate the confidence intervals.”

Oh, Joseph, you kill me. Kirby hasn’t shown the mathematical acumen to figure the tip in a restaurant, much less calculate a confidence interval. He just likes to sound all sciencey by tossing out phrases like “statistically significant.”

I’m not offering an opinion on the numbers, just snorting at the idea of Kirby having the wherewithal to do it.

By: Joseph

Joseph — Sat, 22 Sep 2007 15:58:15 +0000

Schwartz: I’ve been very clear about that in the past. The California DDS provides a wealth of information that is by no means useless. However, it’s important to understand the caveats of the data. For one, the children with an autism classification in CDDS is not the same as the total number of autistic children in California. This is an obvious point. And there is no way to know how accurate the count is, unless you were to do a whole population screening and compare.

So when the data is used as evidence that the total number of ASD children in California has risen, this is clearly an invalid use of the data.

Most children with an autism classification in CDDS do fall in some ASD category. I believe only 1% have been found to be completely outside the spectrum. In that sense, we can say that CDDS counts are a good approximation of a lower bound of the autistic population.

There is other data of interest in CDDS, such as the proportion of autistic children evaluated as having mental retardation. By looking at drops in this proportion, there are indications of what one might call ‘broadening criteria’ or ‘more awareness’.

Now, if David Kirby makes a claim about California DDS data, it stands to reason that a rebuttal would involve analyzing California DDS data.

By: Schwartz

Schwartz — Sat, 22 Sep 2007 14:53:00 +0000

Joseph,

I thought there were so many general problems with the CDDS data that it precludes any meaningful analysis anyways?

Is that still the general consensus?

By: Joseph

Joseph — Sat, 22 Sep 2007 01:23:17 +0000

And another thing is that I’m sure he looked at many different angles. Did the caseload for 4 year olds drop? How about 5 year olds? Could I possibly make a claim about 2 year olds? How about data for March? (Too small a drop there.) October? No good. June – that’s the one.

It’s the same thing he did when he found 4 states with drops in IDEA. As I noted, when he finds 25 states, we can start to talk about leveling off of the IDEA autistic population.
If you look hard enough, you’ll find some fluctuation that on the surface is similar to what you want to show.

By: Sullivan

Sullivan — Sat, 22 Sep 2007 01:08:59 +0000

Kirby has been following the Geier lead in “statistically significant”.

They assume gaussian statistics or something and ignore the historical fluctuations in the data.

Let’s see if/what he comes up with after the next quarterly report.