Stacy Trasancos asked me to review her post “Why Are Catholics Criticizing Dr. Theresa Deisher?“, and in particular the paper “Impact of environmental factors on the prevalence of autistic disorder after 1979″ in Journal of Public Health and Epidemiology by Theresa A. Deisher and four others (Trasancos has links to all the material).
It is Deisher’s (implied) claim that vaccines created (in part) with stem cells “harvested” from the human beings killed for being inconveniences to their mothers are causing an increase in the rate of autism.
There are several matters of interest people are having a difficult time keeping straight. Here’s a list:
- Whether it is, or under what circumstances it is, ethical to kill human beings still living inside their mothers.
- Whether it is ethical to use the tissue from these killed human beings, considering this tissue might lead to more efficacious or cheaper vaccines (which will surely save lives).
- Whether these vaccines might cause any form of autism.
- If so, how likely is it to contract some form of autism from these vaccines.
- Whether it is ethical for Deisher to investigate these claims, given that she might personally benefit (monetarily or spiritually or whatever) from identifying this cause of autism.
- Whether Deisher is a liar, cheat, or a fraud.
Matters (1) and (2) I will not here discuss; they are irrelevant to (3) and (4), which are the subject of Deisher’s paper. Matter (5) is easy: the answer is yes. If it were not, we’d have to fire every scientist everywhere who working for a paycheck, which is to say, all of them. And anyway, claims have to be investigated independent of how they are made. If you rebel at that idea, or automatically dismiss Deisher because of some perceived “red flag”, you are committing the genetic fallacy. Matter (6) we shall come to, but for the lazy among you, I think the answer is no.
Whether vaccines created, in part, from cells “harvested” from dead babies possibly causes any form of autism is a question which I am not competent to answer. I have read enough in the literature to have learned that while there is great and consistent suspicion that they cannot, there is no absolute proof that they cannot; further, Deisher does introduce valid evidence that shows these cells can wreak havoc in other body systems, so it remains possible that (at least some forms of) autism are caused by these cells. But, don’t forget, “possible” is an extremely weak hook to hang your hopes on.
Deisher’s paper is premised on the supposition that “fetal and retroviral contaminants in childhood vaccines” might cause autism. If my reading was shallow, or if anybody else has certain proof this premise is false, now is the time to say it. Otherwise, we must continue.
Now there are many vaccines given to children and at various ages and manufactured by different companies (we are not just thinking of the USA, folks). Even before the vaccine-autism “controversy”, not all kids (in “developed” countries) were vaccinated, though most were. Records on vaccinations are, as far as records go, reasonably good, but not perfect. Records on autism diagnoses, given that there are many forms of autism, are far from perfect, though improving. Kind of.
The key word is diagnoses. Long ago, before autism was well understood, it was, of course, not well diagnosed, so that even if records were immaculate, which they were not, we would not have had a good idea of the actual rate of autism. The increasing centralization of medicine, in teaching, practice, literature, and regulation, undoubtedly contributed to an increase in the diagnosis rate of autism (the reader understands I mean the disease in its various forms; we’ll tighten this later). Indeed, a steady increase in autism diagnoses has been observed.
And then the disease hit public awareness. And then the disease underwent a broadening in definition, especially in the hugely influential Diagnosis and Statistical Manual and its revisions. And then western society increasingly decided that being and acting male was a disease. And then the media was flooded with “Ask your doctor if Profitozol is right for you” articles and ads. And then the Internet hit and facilitated self-diagnoses. And then some wacky celebrities decided vaccines must be causing autism.
The diagnosis rate increased, surely in part because of all these things. But the diagnosis rate could also have increased because something new was causing new cases of autism. How to separate the increase in diagnosis rate from (let us call them) “awareness” factors and actual disease causes? Some thing or things caused each diagnosis, and some thing or things caused each true case of autism. The two sets of causes are different (a doctor identifying a wound is not the wound). Or has the disease definition been expanded so much that even marginal cases are being accurately identified as autism: understand that I mean here accurate diagnoses but for an “autism” that is not be the same “autism” of two decades ago; e.g. every time a boy acts like a boy is now some form of “autism” (or “Aspergers” or whatever).
The Diagnosis and Statistical Manual has been changed many times, and various diseases and maladies have not only changed, but their diagnostic criteria have also changed, in general to broaden them (some jokingly say we’re all mentally ill now). New issues of the DSM are released, as Deisher reminds us, at fixed points in time. But that is not the whole story. The changes to the diagnostic criteria are (or were, up until this newest edition) generally and increasingly known before their actual publication date. After all, the DSM attempts to summarize a known literature, and doctors are free to change their behavior in advance of the new DSMs (which isn’t, anyway, legally binding on doctors).
Point is this: the appearance of new DSMs is not a hard-and-fast “change point” in physician behavior, though it does represent a change of some kind. And even if the contents of new DSMs were completely unknown to physicians until publication dates, not all physicians rush to the bookstore the day these manuals are issued and immediately and wholly change their diagnostic behavior. It takes time for the changes to be assimilated, for new doctors to be trained to come up through the ranks with the new ideas in their heads, and for the dinosaurs who stick to the old ways to die. And so on.
We’re finally back to Deisher, who from her paper does not appear to appreciate these and similar points. I find the paper poor in conception, argument, and quality, and regard her main contention as unproved (which is logically consistent with it is still possibly true).
Here’s what she did. She collected statistics of autism diagnoses rates from various localities and in different forms. Sometimes she examines prevalence, other times incidence, and still other times raw counts. This is confusing. The data sources are not well documented, nor are the procedures she used to construct the eventual data used in her analyses. The “data sources” section in her paper is exceptionally thin, and mostly given over to detailing how she discovered publication dates of the DSMs, which is not disputed by anybody.
Here are one set of pictures she generated (incidentally, the figures in this paper are poorer than is usual in a science journal, and Deisher does not do a good job labeling or discussing them):
The picture on the left is prevalence of autism for the US in the years indicated, and the right is incidence for California. The black lines are the Deisher’s central “finding.” But don’t look at them yet; instead, look just at the dots on the picture on the left, and suppose these are genuine (like I said, I don’t have complete confidence this data is error free).
The diagnosis rate is increasing. Something must be causing this increase in diagnoses. An increase in diagnoses does not necessarily imply an increase in disease presence. The change in “awareness”, as detailed above, is surely a plausible cause in the diagnosis increase. Is it the only cause? Nobody knows. There might be others. Centralization (as discussed above) is one cause. It could be that Deisher’s contention is right and vaccines are contributing to an increase in the disease, which itself is causing an increase in diagnoses, or it could be that global warming is causing a disease increase, or that cosmic rays have been leaking through the atmosphere at increased rates, or it could be anything. Who knows?
The broken black line is the result of a statistical model called a “change-point regression”, a procedure which identifies were breaks might have occurred in data. The eye is drawn to this line, making the “break” appear realer than it would if the black line had been absent. Is there really an increase in the increase in 1980.5? Maybe. Are there really two increases in the increases on the figure on the right? Maybe.
But maybe not. If you subtract away the lines, the breaks are harder to see. Deisher’s point is that these breaks do not correspond to the DSM releases, and thus that something other than awareness must be causing the increases in diagnoses.
There are two big problems.
The first is that, as discussed above, DSM release dates do not cause instantaneous shifts in physician behavior. And anyway, changes to the DSM were not the only changes to awareness, as we saw.
The second is that, even if the change points are real, and even if the other statistics in her paper (which I don’t detail here, as we’ve already gone on too long) are accurate, Deisher has not proved that the cause of the observed changes must be vaccines, especially since the changes in vaccine types were concurrent with changes in awareness.
Deisher nowhere measured which vaccines each child received and which child developed autism, which is the only way to demonstrate potential causality. She only (crudely, too) measured various rates of diagnoses. To conclude the changes in these rates must be from the one cause she posited is to commit the epidemiologist fallacy.
Deisher herself is at least partly aware she has not proved her case, because she admits “While we do not know the causal mechanism behind these new vaccine contaminants and autistic disorder…” But absent any causal mechanism, there is no case.
Obviously, experiments cannot be run on children to see which vaccines might cause which disease. But vastly superior epidemiology can be performed. Specific records on children (including medical history, genetics, etc.) can be kept, tracking when and what kind of vaccines, and so forth. And because this has become a public concern, such things are being done.
Is Deisher a fraud?
Amateurs who have spent no time investigating quacks irresponsibly think all quacks are frauds, or that all bad science comes from scientists with evil motives, or that everybody who makes a claim that turns out wrong is only making that claim for nefarious reasons. Bosh.
Most quacks are not snake oil salesmen. And most scientists who cherish false beliefs (and I must remind us that we have not proved Deisher’s belief is false) are sincere. The homeopathist who sets up shop and the apocalyptic global warming climatologist who submits a grant do so not just because they want to make a buck, but because they believe they are helping mankind. They are not scamming anybody but themselves.
Indeed, the exact opposite is true: these people believe, which is why it is so hard to talk them out of their mistakes.
I have seen no evidence that Deisher is a quack or fraud or that she is lying or that she is ignorant. Instead, there is overwhelming evidence that she is highly intelligent and believes what she is saying. True, she does not help herself by showing up at the Autism One conference, which has more than its fair share of homeopathists and chiropractors, but if we condemned scientists who spoke before screwy audiences, we’d have to fire every researcher who ever appeared on television.
What Deisher’s harsher critics are doing when calling her a fraud or liar is changing the subject (just as do those critics who call global warming a lie or a scam) away from the claim of true interest—do certain vaccines cause autism?—to those of personalities and politics. The claim is forgotten or dismissed with a wave (“only a fool would believe…”) and people are encouraged to take sides without having to do the hard work of thinking.
Update Since it’s come up. What Does The Regression Equation Mean? Causality? and Regression Isn’t What You Think and The Biggest Error In Regression and What Regression Really Is: Part I, II, III. Warning: do not operate heavy machinery while reading these posts.
Deisher’s use of change-point regression is certainly not unusual, but I don’t love it here for the long reasons explained in the new links. It can be and is useful in other contexts. Software geeks can think of it as edge-detection for points.