Thursday, December 8, 2011

Why a Biased Pseudo-Skeptic and False Scientist Should Not Publish a Scientific Review on a Subject He Knows Nothing About.

Some of you may be wondering why I’ve been so quiet lately. In all honesty, I’ve been busy. However, that does not stop me from doing research on various subjects, nor does it exclude me from finding an interesting research article and waiting to see what happens.

Early last month, a new study was released that correlated a link between aluminium adjuvants in vaccines and a surprising number of auto-immune disorders, including Autism. You can read the abstract of the study here.

I waited and watched to see who would try to discredit this study, and how they would try to do it. Our good “doctor” David H. Gorski was the one, and he did not disappoint. Now, I get to have fun picking apart his rambling and monotonous diatribe.

People wonder why I accuse Dr Gorski of pseudo-science and crankery. The answer is simple; he pretends to be a knowledgeable scientist, when in fact, he has no training or legitimate background in many of the subjects he discusses, all while giving the impression that he does. Not only that, but as you’ll see from the below deconstruction, he falls into the exact same traps and fallacies that he accuses others of. Allow me to demonstrate.

In his rambling and spittle-flecked rant entitled And global warming is caused by the decrease in the number of pirates or: Why an inorganic chemistry journal should not publish a vaccine epidemiology paper, he begins with a mocking dissertation on how much fun he’s been having with “anti-vaccine cranks” over the past few days. Observe:

“In my eagerness to pivot back to an area of my interest after having had a little fun with anti-vaccine cranks, I ignored a paper to which several of my readers referred me over the last few days. Many of them had first become aware of it when everybody's favorite smugly condescending anti-vaccine crank, Ginger Taylor, started pimping it on her blog.”

While he smugly and condescendingly does the same. Continuing:

“Before that, it apparently popped up on the only anti-vaccine site almost as loony as Age of Autism, namely SaneVax, and it wasn't long before this paper started making the rounds of the anti-vaccine crankosphere, showing up at Gaia Health, and then just yesterday the anti-vaccine propaganda blog Age of Autism. It was at that point that I decided that I had made a mistake in not taking a look at this article; so I was more than happy to do so.”

I’m sure you can all see what he’s doing here and I’ll allow you the opportunity to read that paragraph again, knowing that he is attempting to color his readers’ opinions on what the article will contain. Poisoning the well, anyone?

He duplicates the abstract, and then follows with this:

“I thought I knew all the major quackery websites out there, but somehow I had never come across this one before. It appears to be a doozy, posting a glowing review of the anti-vaccine movie whose misinformation and pseudoscience I deconstructed three weeks ago, attacks on Brian Deer for his exposing Andrew Wakefield for the fraud he is, and, in a classic case of crank magnetism, a heapin' helpin' of anthropogenic global warming denialism.

Already, things aren't looking too good.”

Indeed, Dave, they are not. Look here, my friends. He further attempts to color his readers’ opinions on what the article actually contains, not even bothering to discuss the actual science. Moving on:

Still, I pride myself on always going straight to the source when examining studies like this that are being bandied about the anti-vaccine underground. Who knows? Maybe I'll find something to change my mind. True, it's highly unlikely, but you never know (Gambolputty – Oh, dear…I got a lovely chuckle out of that one!). I was, however, curious just who the authors are. Christopher Shaw, I had heard of before. He was featured in the anti-vaccine propaganda movie The Greater Good and gave a talk at the anti-vaccine conference in Jamaica featuring Andrew Wakefield in January. His co-author Lucija Tomljenovic is apparently a postdoctoral fellow who was also a speaker at that very conference, giving two talks there.”

More of what I mentioned above. And that is just the introduction! Not only that, but we have a heaping helping of an ad hominem fallacy and guilt by association mixed in, don’t we?

Already, we see that he has established that he is biased against the paper. A real scientist would read the paper objectively, not with the antagonistic bias we see here.

So let's get to the meat of the article, such as it is. Personally, after reading it a thought kept going through my head, namely that chemistry journals (particularly journals devoted to inorganic chemistry) probably shouldn't be publishing medical articles. The editors and peer reviewers, so enamored with an apparently strong correlation, fell for the oldest crank gambit in the book: Confusing correlation with causation. Perhaps the most irritating part of the article is how Tomljenovic and Shaw misuse and abuse Hill's criteria, a famous set of nine criteria postulated by Sir Austin Bradford-Hill for assessing the plausibility and likelihood of a particular correlation indicating causation. I discussed Bradford-Hill's criteria before when Andrew Weil also misused and abused them.”

Finally, he starts discussing his interpretation of the science. Notice his sneering contempt for a legitimate research journal. Can anyone see the huge and glaring error he made in the above paragraph? Don’t scroll down until you can see what it is.

That’s right. He accuses the authors of the article of confusing correlation with causation. Let’s look at the relevant sentences that state what the authors concluded, shall we?

“The application of the Hill's criteria to these data indicates that the correlation between Al in vaccines and ASD may be causal. Because children represent a fraction of the population most at risk for complications following exposure to Al, a more rigorous evaluation of Al adjuvant safety seems warranted.

The emphasis is mine. It’s interesting…they say that the correlation requires more study, and that the correlation may be causal, not that it is causal. Notice how he twists and manipulates what is actually said in the conclusion. In any study that comes to this sort of correlation/conclusion, it is an excellent idea to study the correlation more concretely. His invocation and interpretation of the Bradford-Hill criteria will be approached further down. Keep in mind that Gorski’s interpretation of the criteria is, in his monochromatic view, the only interpretation that matters. Let us continue.

Perhaps the silliest aspect of this article is Table I, in which Tomljenovic and Shaw try to convince you that the inflammatory aspects of various autoimmune diseases share aspects with inflammation provoked by aluminum adjuvants. Of course, I'd be shocked if some autoimmune diseases didn't share some aspects of inflammation provoked by aluminum adjuvants or even vaccines in general. Inflammation is a common process that can be provoked by many things. I could tell you that the cytokine profiles that Tomljenovic and Shaw point to as being so "similar" to cytokine profiles due to aluminum adjuvants are the same sorts of cytokine profiles that result from almost any sort of injury. If, for example, as a surgeon I cut open your abdomen in order to rearrange your anatomy for therapeutic intent, I bet I could find studies with cytokine profiles that I could tenuously compare to cytokine profiles due to vaccination with aluminum-containing vaccines.”

This is an interesting argument. However, the fact that these markers were present is cause for concern. These markers should not be present in anyone if vaccines were as safe as Mr Gorski would like you to be brainwashed to believe. The authors even go so far as to provide links to previous studies that corroborate their reasoning. I’ll get to those shortly. For now, we will continue with Gorski’s analysis.

In fact, perusing the chart I'm struck by how tenuous the resemblances between inflammation due to autoimmune diseases and inflammation due to aluminum adjuvants is. Presumably this is the best these two could come up with, and their best just isn't all that convincing. None of this stops the not-so-dynamic duo from including autism and Gulf War Syndrome on their list. The latter they characterize as being "specifically recognized as 'Autoimmune/inflammatory syndrome induced by adjuvants," which is news to me given that I thought the emerging consensus was that Gulf War Syndrome probably doesn't exist as a single distinct syndrome but rather as many health problems with different etiologes, much less is it recognized as some sort of autoimmune syndrome caused by vaccine adjuvants. After all, none of the anthrax vaccines soldiers received prior to going to the Gulf used squalene adjuvants. Meanwhile, autism spectrum disorders are listed in the chart as being "linked to Al-adjuvanted vaccines." I suppose that's true in the literal sense in that anti-vaccine activists have linked ASDs to Al-adjuvanted vaccines, but what Tomlijenovic and Shaw are doing is what lawyers like to call assuming "facts not in evidence." Again, there is no solid evidence linking vaccines, whether Al-adjvanted or not, to autism, and several large epidemiological studies that have utterly failed to find a link between vaccines and autism. Where were the peer reviewers here?”

Ok, this will take a little bit of time to deconstruct. Bear with me here.

Let’s begin with GWS, or Gulf War Syndrome. He states that none of the vaccines given to veterans before going to the Persian Gulf contained squalene-based adjuvants. He gives no reference to this, of course, but fortunately I was able to track down what he was talking about, which was an IOM funded study released in 2006. What he fails to mention (or deliberately omits) is that an FDA investigation in 1999 found 5 specific lots of Anthrax vaccines that contained squalene adjuvants. So, there is some controversy there.

However, let’s give Gorski the benefit of the doubt and say that his statement is somewhat true. Even if we take that position, then the authors’ statement is also true in that there has been evidence of adjuvants having been linked to GWS and autoimmune disorders in gulf war veterans.

Taking this position, then we can also say that there has been some data linking autoimmune dysfunctions in autistic children and that these dysfunctions have been linked to vaccines. Need I mention a certain beautiful little redhead we all know and love?

The "evidence" in the paper consists mainly of Tomlijenovic and Shaw comparing increasing ASD prevalence to the increasing number of vaccines in vaccine schedules in various countries, their argument being that increasing doses of aluminum through vaccines correlates with increasing prevalence of ASD. Basically, they collected data on ASD diagnoses for children from ages 6-21, from 1991-2008 from the US Department of Education Annual Reports for ASD prevalence. Next, they tried to correlate the autism prevalence in this group with the cumulative aluminum dosage they received before age 6 through the pediatric vaccination schedule. They then basically did the most simplistic analysis imaginable, plotting the minimum, mean, and maximum aluminum exposures against ASD prevalence. Can you say "ecological fallacy"? Sure, I knew you could.”

It’s fortunate that the authors used very simplistic means to plot their data. It clearly and succinctly shows a distinct correlation that in no way can be refuted. Dave attempts to do this in the most hilarious and hypocritical way; by invoking the Ecological Fallacy. He’s even kind enough to define that for us.

“To recap, because I haven't had to discuss it in a while, the ecological fallacy can occur when an epidemiological analysis is carried out on group level data rather than individual-level data. In other words, when the group is the unit of analysis, the chances of finding a false positive correlation go way, way up”

Can any of you think of any epidemiological studies released by the CDC and the Pharmaceutical industry that falls into this fallacy? Can you say all of them? Sure, I knew you could.

Add to this the fact that, for all the authors' claims that they controlled for confounding factors, by falling for the ecological fallacy they allowed huge confounders into their analysis. Even worse, they appeared to make no attempt to control for birth cohort other than to remove vaccines from their calculations that hadn't been introduced into the schedule at the time the children were vaccinated. (How nice of them.) In any case, although the diagnostic criteria used for autism and ASDs were set in 1994 in the DSM-IV, screening in schools, increased availability of services, and decreasing stigma to a diagnosis of autism led to an explosion in autism diagnoses. The way to control for this would have been to examine much more narrowly defined birth cohorts. They didn't. They used a single 15-year period. They also did nothing more than look for a linear correlation between aluminum dose and autism prevalence, citing r = 0.92, instead of calculating r2. The authors are incredibly impressed by this (and apparently so were the reviewers), even though it's not so hard to produce high Pearson coefficients for a lot of seeming correlations that in fact don't have anything to do with each other. The most heinous example I can recall is a ham-handed attempt to correlate abortion rates with breast cancer incidence.”

This is a somewhat absurd argument, isn’t it? This is a single correlative study that looks at a particular hypothesis and investigates correlations between a potential cause and effect. It is certainly not uncommon for such a preliminary study to congregate such data into a single cohort. In fact, plotting the data year by year (as was done here…I’ll post the chart shortly) reduces the chance of the same statistical manipulations that we saw in the Madsen studies. Here’s the chart:

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Hard to refute the numbers, yes?

Given how common papers like this are from anti-vaccinationists are, I sometimes think it would be fun to play a game I'd like to call "Name That Correlation!" What other correlations with the increase in autism diagnoses can we find over the last 20 or 30 years? Let's see. Personal computer use has been rising since the 1980s. Perhaps that's the cause of autism! More similar to Tomlijenovic and Shaw's time frame, Internet use has exploded since the early 1990s. Back in 1990, few people had Internet access or e-mail addresses. (As hooked in as I am now, believe it or not, I didn't have Internet access back then, either.) Now almost everyone does, and Internet access has become truly mobile via smartphones like the iPhone, Blackberry, and Android handsets. I bet a nice correlation between Internet usage and autism diagnoses could be constructed. Come to think of it, mobile phones, although first introduced in the 1980s, didn't really begin to take off until the mid-1990s. In the early 1990s, mobile phones were uncommon because they were so expensive and coverage was very spotty. Now, the nearly everybody owns one. The time frame of Tomlijenovic and Shaw's study fits the time frame of the rise of mobile phone use almost perfectly!”

Funny he should say this. My friends and I have created a game that is quite similar. We take these studies that show a correlation between vaccines and autism, and then take bets to see who will be most accurate with how the pseudo-skeptics and false scientists will attempt to refute it. The most humourous aspect of Gorski’s comment is his attempt to refute the evidence based on other things that could be responsible. The problem is, internet usage and cell phones have never been known to cause encephalitic reactions in children within hours of usage. I can certainly think of something that has, though. Can’t you?

Finally, Tomlijenovic and Shaw misuse and abuse Bradford-Hill's criteria. For example, they list criteria numbers one and two as being satisfied for aluminum and autism. Those are strength and consistency. The problem with these criteria is that they aren't supposed to be evaluated by one study. They conclude their association is strong because they have a high Pearson correlation coefficient, but their study is an outlier. It's not correct to say that the correlation is strong based on the totality of the evidence. Ditto for consistency, as, again, their study is an outlier, and, quite frankly, citing DeLong's execrably embarrassing study as a study that found a correlation between vaccine uptake and autism does not help their case. They also try to convince readers that one of Bradford-Hill's other criteria, such as biological rationale and coherence, have been met because of their attempt to make the tortuous vague resemblances between cytokine profiles they constructed seem like strong evidence for biological plausibility. Even worse, they try to use their confusion of correlation with causation as an argument that there is a temporal relationship between the purported cause and the effect. No, it's not. In fact, they have not convincingly met any of Bradford-Hill's criteria, much less eight out of nine.”

Ah, we finally get to Gorski’s biased interpretation of the Bradford-Hill criteria. I’ll give him the point that criteria one and two should not be determined by just one study, however, the Bradford-Hill criteria do not specify that the study shouldn’t be an outlier; this appears to be Dave’s own interpretation. But let’s go one step further and evaluate what is stated in the study.

Under Strength, they say that the association is statistically significant (consistent with the Bradford-Hill criteria for strength (here)). Looking at their data, then this falls within the criteria, so they’ve marked it as a “Yes”

Under Consistency, they say that several studies have found an association between vaccines and autism (true). Following the criteria (replication in other studies), then this is also given a “Yes.”

They gave sufficient reason for biological rationale in that there is a demonstrable association between auto-immune dysfunctions and cytokine response (this is a verification of Dr Poling’s work).

Here’s the table that shows how the authors demonstrated the Bradford-Hills criteria:

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It’s clear to me that Mr Gorski does not like the results of this study. In fact, it’s quite clear that he began his analysis without an objective mind and used his own bias and misinterpretation of the Bradford-Hills criteria to make his own judgment on what the article is actually saying. For example, he repeatedly accuses the authors of confusing correlation with causation, when the authors do nothing of the sort. They clearly state that Aluminium adjuvants may be associated with autism and auto-immune disorders and give statistics and data to show how they came to this conclusion. I always enjoy how Dave likes to build strawmen and put words in peoples’ mouths.

In conclusion, I’d like to give you a definition of a pseudo-scientist and a crank.

  1. Cranks overestimate their own knowledge and ability, and underestimate that of acknowledged experts. (Gorski gives the firm impression that he’s an expert, and he dismisses anyone who disagrees with his view, despite them being real experts)
  2. Cranks insist that their alleged discoveries are urgently important. (Gorski insists that all scientists agree with him, and any scientists who does not agree with him is not a real scientist)
  3. Cranks rarely if ever acknowledge any error, no matter how trivial. (Self explanatory)
  4. Cranks love to talk about their own beliefs, often in inappropriate social situations, but they tend to be bad listeners, and often appear to be uninterested in anyone else's experience or opinions. (How often does he blog? And the last half is self explanatory.)

I’d also like to add another; a crank dismisses evidence that does not conform to their pet theory, or evidence that they dislike. They will attack this evidence with an unmitigated rage.

Doesn’t this sound familiar? Any questions as to why I say David H. Gorski is a crank and a quack?

6 comments:

  1. I was wondering if you'd tackle this. Well done!

    I made a comment on Ginger's blog a few weeks ago about this study:

    http://adventuresinautism.blogspot.com/2011/11/do-aluminum-vaccine-adjuvants.html

    "I wonder how long it will be before Orac and his slobbering dolts will dismiss this as pseudoscience (by not reading it, of course). $5 says that Dorkski will be spewing about how the author of this study is "anti-vaccine" because the idiot doesn't like the results. Especially since the study doesn't agree with his own confirmation bias."

    And I was spot on, too.

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  2. If vaccines are producing inflammation on a level with surgery there really is a big problem. I wonder if Gorski meant that the way it sounded?

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  3. Ah, Craig. Have you seen this study?

    http://www.termedia.pl/Original-paper-Lasting-neuropathological-changes-in-rat-brain-after-intermittent-neonatal-administration-of-thimerosal,20,15811,1,1.html

    Here's my prediction on this one. One (or more) of the following will be said to discredit this paper:

    1. Numerous "well designed" epidemiological studies over the past 10 years have clearly shown that Thiomersal in vaccines is perfectly safe and beneficial (all bought and paid for by groups with vested interests).

    2. Thiomersal was removed from childhood vaccines in 2001 (or 2002, or 2003...they can't seem to get the exact date right on that one), and the rate of autism has continued to increase, so it cannot be Thiomersal (despite the fact that the CDC and doctors pimp out flu shots, with full 25 mic dose of thiomersal, to everyone every year starting at 6 mos. That thiomersal doesn't count).

    3. 6 degrees of Kevin Bacon...err separation where Gorski and his drooling minions attempt to associate one or more of the authors with this or that anti-vaccine group because one of the authors once shook a known "anti-vaxxer's" hand.

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  4. Gambolputty you left out the flu vaccines pimped to pregnant women. Gotta get a dose into the fetus while they are still in the womb.

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  5. As I said, Minority...that doesn't count ;-)

    I've been slumming to see if anyone has tried to discredit this yet. Nothing so far.

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  6. One other thing I find very puzzling is that the same people who say that rates kept increasing after the removal of thimerosal (whenever that might have been) are the people who say there has been NO increase in autism.

    Six impossible things before breakfast?

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