Monday, October 30, 2006

Autistic Teens Being Taught They Are "Recovered"

Thanks largely to the magic of YouTube, it's now possible to see what people mean when they claim that autistic children have "recovered" from autism. There are several videos with such children which can be found in YouTube. I'll post a couple here, without naming any names.

What do readers think? Obviously autistic teens are being taught essentially that it's bad to be autistic but they shouldn't worry about it because they are "recovered" now. Is this good, bad or indifferent, considering these teens are probably able to pass (with an unknown amount of effort)?

In a letter to BMJ, a psychiatrist named Sami Timimi provides an anecdotal account of autistic teens asking to be undiagnosed:

In my clinical practice I often come across children and adolescents who are labelled autistic. When I focus on their abilities I often find much about them that does not fit the autistic discourse. Once I reopen the question of diagnosis many adolescents ask me to officially "undiagnose" them, which their parents are usually very pleased about.

I can see why a teenager might not want the "autistic" label. And it's not surprising that most parents would be pleased, even though the child is the same child before and after the label is removed. But there's obviously something wrong with this, in a social sense.

Wednesday, October 25, 2006

An Island of Rationality

The following was overheard in EOHarm recently:

However, unless mercury is somehow being slipped into children in greater amounts now than in the 90's, mercury does not seem to be the main cause of autism now. And no, I don't think the mercury in the flu shots is capable of offsetting the mercury infants got at birth, 2, 4 and 6 months in the 90's. Flu shots present smaller doses at later ages, and the big flu shot push for kids didn't get started until 2004 anyway.

The message has not had any replies, and it's not clear if the person who posted is still in the list after such a blasphemous remark.

This was written by someone who does believe vaccines have "almost everything to do" with autism. But this person does take the time to look at the actual CDDS numbers and not just claims about the numbers, and clearly has some skills that allow her to interpret the numbers. For her critical thinking, she should be commended.

I should note that she claims to believe in the work of the Geiers, which is actually inconsistent with her analysis of the CDDS numbers.

She expresses concern about the "57% increase in the 3-5 year olds" (in the last 4 years). And makes a good case about prevalence, which follows.

Let's assume the 1 in 166 for ASD (which includes Asperger's and PDD_NOS, not included in these numbers) is going to be close to what you would get based on people that were 3 to 21 in 2002. The US Census Bureaus says that California has approximately 500,000 people of each age in the younger ages – or 57,200 people with ASD. The 2002 full autism numbers for ages 3 to 21 add up to 15,939, or about 27.9% of the ASD population and also about 1 in 600 for the entire age cohort. The 2006 group of 3-5 year olds represents 0.41% of the California population age 3-5. If you assume these number will increase 62% in the next 4 years, as did the 3-5 group from 2002, you get 0.67% of the population, or 1 in 150 -- FOUR TIMES THE CURRENTLY REPORTED RATE!!!

I do also share her concern that the current prevalence of 40 in 10,000 for the 3-5 cohort is higher than expected for Autistic Disorder, and this prevalence is still growing at a fast pace. That is, it's not clear when it will level off, and we can't assume there's a magic number it cannot go over. But it's not as bad as she thinks. Anecdotally, some PDD-NOS and Asperger's does get included in the CDDS numbers. Besides, in psychology there's a debate about the existence of Asperger's. Some researchers are saying that DSM-IV Asperger's is impossible to diagnose, and that virtually all children diagnosed with Asperger's actually have Autistic Disorder. If this opinion becomes mainstreamed, what do you think the end result might be in terms of caseload?

Additionally, it's unlikely that the 62% increase will be maintained over the next 4 years. Growth expressed as a percentage necessarily decreases over time.

She adds:

We really [need] to get to the bottom of this. The effects on society are almost too big to contemplate.

The fact that more and more children are being labeled with all sorts of cognitive disorders is a valid concern, in my opinion. Sami Timimi, for example, is an outspoken critic of psychiatric over-labeling. He says that we'll end up with a generation of grown-up children who have been unnecessarily convinced that they are defective. But should we be concerned about an increasing number of people becoming disabled? I think we should be really concerned about this if, say, the prevalence of institutionalized developmentally disabled individuals were increasing. (However you look at it, more institutionalization is not a good thing). But it's not increasing. In fact, it has dropped a little in the last 14 years in California, according to the CDDS numbers. If our concerns are not consistent with reality, what is the use of our advocacy?

Saturday, October 21, 2006

Precipitation Rates vs. Population Density in Pennsylvania

Criticism of the autism-TV study out of Cornell has so far focused on the perceived plausibility of the hypothesis, and on author credentials, for the most part. For example, it has been pointed out that autism is present since birth/conception (or acquired in utero). If only it were that easy to dismiss post-natal environmental trigger theories these days.

The study was thought to be a prank at first, due to its peculiar methodology, but it's clear by now that it is not meant as a joke. Apparently, a lot of work went into it.

The authors of the study are economists, and this seems to be taken by many as a quick way to dismiss the study altogether. I would note that they are not the first authors of an epidemiological study on autism who are not trained in autism epidemiology. I think the study needs to be considered and critiqued on its merits.

Alternative interpretations have been proposed. Perhaps humidity causes autism, through mold and mildew, for example. Maybe spending time outdoors is a preventive measure. And so forth. These alternative interpretations, nonetheless, simply switch one hypothesis with another of equally unknown plausibility.

What I'd like to do in this post is propose an interpretation of the results based on a hypothesis known to be plausible, and which has been documented previously. Namely, that the results can be explained by a established correlation between degree of urbanization (or population density) with the administrative prevalence of autism. I already did something similar in a critique of the environmental pollution hypothesis.

That cable subscription rates are correlated with degree of urbanization or population density is a sure bet, and I won't consider that further. A potential correlation between population density and annual precipitation is non-obvious, however, although I had previously suggested that people generally don't build communities in the dessert.

I will use the state of Pennsylvania for this post, simply because there's readily available data on administrative prevalence with high regional granularity from that state. The authors analyze California, Oregon and Washington for precipitation. Readers can check if the analysis holds in those states. Fortunately, I didn't have to do much work to get the data I'm about to present, save for a few Google Image searches. Let me first post images modeling annual precipitation in the state of Pennsylvania.

Figure 1. Annual precipitation in Pennsylvania
(found at

Figure 2. Annual precipitation in Pennsylvania
(found at

Now, let me post an image with modeling of population density, and an image which shows the location of major cities in the state of Pennsylvania.

Figure 3. Population density of Pennsylvania counties
(found at

Figure 4. Pennsylvania road system, showing major cities
(found at

Already we can see there is a fairly clear correlation between precipitation and population density in part of the state, perhaps even in 2/3rds of the state taken from East to West. Such a correlation is not at all clear in the West side of the state, but the correlation in the East side is probably enough of a confound.

Let me now post an image modeling autism prevalence across the state of Pennsylvania.

Figure 5. Pennsylvania IDEA autism cases per 10K enrolled
(found at

A correlation with either population density or precipitation is not that clear at first glance, is it? Let's focus on the bluest patches of prevalence, and let's compare with the Pennsylvania road map. You will note that high prevalence tends to coincide with urban areas, namely, Philadelphia, Harrisburg and Pittsburgh. Pittsburgh is particularly interesting, because it's an area with low precipitation. That's on the West side of the state, where I noted that a correlation between precipitation and population density was not clear.

Admittedly, there is an area near Erie (North-West corner) where there is high precipitation and high autism prevalence, but population density does not seem to be exactly where you would expect. This data point throws off my argument a bit, but it's not much to go on.

Going forward

The correlation between administrative prevalence of autism and population density lends itself to false correlations between autism rates and innumerable proposed contributing factors in autism. It would be extremely easy, for example, to "prove" the autism fries hypothesis using this type of analysis. In the future, regions with equivalent population density and wealth should be compared. Additionally, studies should be devised to determine if differences in autism prevalence between regions are actual or simply administrative.

Note: I plan to email Dr. Waldman and refer him to this post.


I thought I would share a couple of remarkable images modeling annual precipitation and population density in the United States.

Figure 6. Annual precipitation in the U.S.
(found at

Figure 7. Population density in the U.S.
(found at

If you've ever wondered why population in the U.S. distributes the way it does, here's a big part of the answer. I have noticed that it's not so much that precipitation positively correlates with high population density, but that lack of precipitation correlates rather well with low population density. This is fairly obvious in retrospect.

Friday, October 20, 2006

Neurodiversity Trying to Steal "Autism" from the Disabled

Michelle Dawson and Laurent Mottron recently participated in an excellent radio segment titled Rethinking Autism in a CBC radio show called Quirks and Quarks. In it they discussed a new model of autism as a type of person, in contrast to the prevailing model of autism as a broken normal person.

Lenny Schafer, posting on Tue Oct 17, 2006, in the mailing list EOHarm, reacted to the program as follows:

The neuro diversity campaigners continue their efforts to redefine autism as not a disability, but a personality trait we just all need to learn to live with. This is nothing more than the crass exploitation of the disabled and needs to be called out as such. They are trying to steal "autism" from the disabled.

My first reaction to this was to think that Lenny Schafer is trying to steal "semantics" from grammar. No, seriously, I'm not sure I understand what he's trying to say.

Maybe he is saying that all anti-cure autistics are not disabled, but all pro-cure autistics are disabled? And that we are trying to steal the "autism" label from pro-cure autistics?

Or perhaps he thinks the autism rights movement is at odds with the disability rights movement? Is it? I wonder what deaf people think of autism rights, for example.

Friday, October 13, 2006

CDDS Q3 2006: Thimerosal Hypothesis Still Dead


Back in November, 2005, David Kirby agreed with blogger Citizen Cain on the following:

If the total number of 3-5 year olds in the California DDS system has not declined by 2007, that would deal a severe blow to the autism-thimerosal hypothesis.

Let me emphasize that David Kirby also conceded that what matters is the total number of 3-5 year-olds, not changes in caseload growth. As I have argued, drops in caseload growth should be expected in the long run anyway.


With one quarter to go before 2007, the latest quarterly report is out, as first blogged by Dad of Cameron. Please check out his graph of the 3-5 cohort caseload for the last 17 quarters.

Here's a table with some of the highlights from the last 4 quarters.

Table 1: State-wide comparison of Q3 2006 with three prior quarters.
(False New Cases)
Annual Growth (%)3-5 Cohort
Q4 200529,42470010.72%5,680
Q1 200630,18175710.50%5,827
Q2 200631,01283110.56%6,083
Q3 200631,85384110.89%6,188

The key information in Table 1 is that the 3-5 caseload continues to grow, and this growth is still rather fast compared to population growth in the state of California. Barring any miracles, in one quarter David Kirby will either need to issue a statement saying that he no longer believes in the autism-thimerosal hypothesis, further goalpost-shift the target date for a caseload drop, or claim that there hasn't really been a significant drop in the thimerosal dose per child in California. What do readers predict he will do?

It's a bit surprising that caseload growth has increased for at least the last 4 quarters in a row. Even when expressed as an annual percentage, it seems to be in an upward trend. As I've noted before, this might indicate that leveling off of the population (i.e. annual caseload growth matching California population growth of about 1%) is still very far away.

CDDS autism prevalence for the 3-5 cohort is currently about 40 in 10,000. This is not supposed to include PDD-NOS or Asperger's, but anecdotally it is known that diagnoses are changed in order to force eligibility in some cases.

Thimerosal Hypothesis

It is important to understand what the "thimerosal hypothesis" is. Versions vary slightly, but let's take Mark Blaxill's one, as presented to the IOM in 2001. Blaxill indicated that mercury exposure from vaccines went from about 70 micrograms for the 1991 birth year cohort to about 180 micrograms for the 1994 birth year cohort, which coincided with an increase in the prevalence of autism for birth year cohorts between those years. That is, most or all of the prevalence increase during the "autism epidemic" of the 1990s can be attributed to an increase of the thimerosal dose per child, according to Blaxill.

Were Blaxill's hypothesis correct, if thimerosal exposure drops to levels below 70 micrograms, the 1990s epidemic of autism should be reversed. Even if you believe there are still traces of thimerosal in vaccines, and that children are still exposed to 25 micrograms of thimerosal from the Flu vaccine, it is clear that thimerosal exposure is no more than it was in 1991 and the entire 1970s and 1980s for that matter.

Note that the 3-5 CDDS autism caseload in Q2 1992 was 462. That is about 13 times less than what it is today. There is no denying such clear numbers. The only way to continue to believe in a hypothesis such as Blaxill's involves suspending reason. At this point we are simply waiting for the main proponents to come clean on that, provided intellectual honesty means something to them.

Wednesday, October 11, 2006

Coming Out Day Video

This video is about human rights from the gay rights movement's perspective. But I'm sure many readers will find it applicable.