By Mary Webster
During the last several weeks, Mark Blaxill has shared with us his commentaries on the reanalysis of a study originally published by Ip et al in 2004 in the Journal of Child Neurology. (HERE and HERE) You may recall that a pair of researchers from the University of Northern Iowa, Catherine DeSoto and Robert Hitlan, discovered serious flaws in the study and took their concerns to Dr. Roger Brumback, Editor-in-Chief of the journal.
To his credit, Dr. Brumback not only asked DeSoto and Hitlan to re-evaluate the data from the original study, he published their analysis along with a candid explanation of the errors Ip and his colleagues made. In the spirit of full disclosure, Dr. Brumback also included in his note the raw data from that study.
As Mark pointed out, the original researchers made errors that were not simply typographical in nature, they also committed grievous mistakes in analyzing the data and in the conclusions they drew from the studies' results. DeSoto and Hitlan found that the study demonstrated quite convincingly that the children with autism were excreting less of the mercury to which they were exposed and children with autism had more mercury in their blood than the controls. These findings stand in stark contrast to those of the study's original authors who claimed, "…the results from our cohort study … indicate that there is no causal relationship between mercury as an environmental neurotoxin and autism."
Ip and company not only concluded there was no evidence of higher mercury levels in children with autism when compared with typically-developing children, they also used the opportunity to take a swipe at those who claim chelation may be an effective treatment for autism. In their concluding paragraphs, the authors wrote, "Some have proclaimed that chelating therapy for suspected mercury poisoning cures those autistic children with a higher mercury level. Our pilot study demonstrates that this is not based on hard-core evidence." That's a bold statement, even if the data supported their findings, which it clearly doesn't. This none-too-subtle comment also serves as an indication of the researchers' inclination on the subject.
For another clue as to the relevance of this study in the greater mercury-autism debate, we need only turn to Professor Wong's body of work. Virginia Wong, the corresponding author in the Ip study, also participated in a study published in the journal Neuropediatrics in 2006 in which she examined the mercury levels of children with ADHD. In this study, Professor Wong and her co-author, Daniel Cheuk, concluded that one might expect to find increased mercury in children with ADHD which, they surmised, could be linked directly to the exposure of methyl mercury from fish consumption. In the study of children with ADHD, Professor Wong and Dr. Cheuk found higher levels of mercury in the blood of children who had ADHD than children who did not -- just as they had anticipated.
Interestingly, in their 2006 study, Wong and Cheuk mention Wong's 2004 study during their brief discussion of thimerosal and assertions by some that there may be a link between mercury in vaccines and neurological dysfunction. Professor Wong, obviously, saw the Ip study on mercury and autism as a test of this theory and, as they assumed it would, the study failed to support an association between mercury and autism – or did it?
This leads to an interesting and important question - If children with ADHD have increased blood mercury levels when compared to children without the disorder, is it appropriate to include these children as typically-developing controls in a study evaluating the mercury levels and excretion patterns of children with autism? One would expect to get a more accurate picture of whether or not there is a connection between mercury and autism from a study in which children with ADHD are expressly excluded.
So, Mark and I have filled you in on some of the errors and misinformation found in the Ip study, but these mistakes were inconsequential, right? I wish I could reassure you that this mess of a study was overlooked by the scientific community. Unfortunately, I can't.
While it attracted little attention in the media and few have even heard of it, I was surprised to learn which noted scientists have used these results in their own research. Paul Shattuck, Craig Newschaffer, and Eric Fombonne are among the most familiar on the list.
It is interesting to see just how far this relatively small, pilot study actually traveled. Additional assorted publications in which one might find the Ip study range from a position paper out of Hong Kong College of P aediatricians on chelation therapy and mercury and lead exposure in children (Hong Kong Journal of Paediatrics, 2004) to a review of developmental neurotoxicology ( Journal of Neuroscience Research, 2005) to a report to the Texas legislature on mercury in that state (Mercury in Texas: Background, Federal Rules, Control Technologies, and Fiscal Implications, September 2006).
Several particularly troublesome examples of the Ip study's fortitude come to us out of Canada. Eric Fombonne, a psychiatrist and noted autism researcher from McGill University in Montreal, co-authored two articles in 2006 in which he cited the Ip study. In Autism and MMR Vaccination or Thimerosal Exposure: An Urban Legend?, published in the Canadian Journal of Neurological Science, Fombonne, along with co-author, Michael Shevell, writes an editorial teeming with certitude. "Biological studies," he states, "have also not validated any thimerosal and autism link."
Fombonne concludes his comments with,
Parents of autistic children deserve answers to the question; "Why their child?" The answers to such a question lies not in chasing phantoms and legends, but rather pursuing early promising leads offered by recent advances in molecular genetics and neuro-imaging.
Clearly, if Dr. Fombonne has his way, we can expect a future filled with more of the same research focused on genetics and the brain. Who needs to be troubled with the gut, the glands, or the immune system? And he supports that recommendation, in part, using the original Ip study results.
And this raises an intriguing issue related to scientific research – the way in which existing research guides future research. Obviously, the original findings of the Ip study, at least in a small way, have influenced some researchers when determining whether or not additional investigation into a possible connection between mercury and autism is warranted.
So, let's take a look at the purpose of scientific research.
During a presentation at the National Autism Association's conference last month, Dr. Tom Insel, director of the National Institute of Mental Health, concluded his formal remarks by sharing with his audience the goals of science, as he and many of his fellow researchers at the National Institutes of Health see them.
"One of the chief causes of poverty in science is imaginary wealth. The purpose of science is not to open the door to an infinitude of wisdom but set some limit to the infinitude of error." - Brecht, Life of Gallileo
Now, I started my remarks by telling you that we know a very small part of what we need to know. I would imagine it's under 10%. Many of you think you know the answers and we want to hear those. But I want you to understand that we set a very, very high bar in science - that most of what we do in science, as somebody once said, is "1% inspiration and 99% perspiration." So, it takes three months to make a finding and ten years to try to falsify it before you really believe it. Some of you don't have ten years to wait. I understand that. But, our goal, here, is to make sure we do set a very high bar and that when we tell you something, it's something that we know can be replicated not just for your child, but for many, many other children, because there's a lot at stake. So, the idea of setting a limit on the infinitude of error is extremely important to us and is a sort of guiding principle to make sure that we are trying to test as many different ideas as possible, but putting a very high bar on what we would accept as a test of any given idea before we feel that it's proven.
Limiting the potential for error in science is, indeed, a lofty goal, but remember Dr. Brumback, Editor-in-Chief of the Journal of Child Neurology? In his note accompanying the erratum for the Ip et al article, Dr. Brumback states, " One of the philosophical myths associated with science is that invalid information published in scientific journals will be exposed by scientists who find that a particular study cannot be replicated. Unfortunately, this is rarely the case." He continues,
…interest in replicating the published results is lacking because there is no glory in being the second person to describe a particular phenomenon, and research funding agencies (such as the US National Institutes of Health) do not provide grants to investigators wanting to confirm the results of other investigations. Thus, it is actually a fluke when problematic publications are identified.
So, errors in science are often missed because funding is rarely allocated to research designed to replicate a previously-obtained result. It's a "fluke" that DeSoto and Hitlan found these. This reality seems a far cry from the pristine world of science Dr. Insel describes.
If limiting error is, truly, of utmost importance in science, we should expect to find a number of retractions and corrections following DeSoto and Hitlan's article. It's been three weeks and what have we heard? A flurry of short-lived posts by a few bloggers and that's about it. From officials in various government agencies cloaked in the mantle of science we've heard nothing but ear-splitting silence.
There has been one bright note, however, courtesy of Congressman Dan Burton of Indiana. Congressman Burton, you may remember, held hearings while Chairman of the House Committee on Government and Reform. During the hearings, the committee considered the possible role mercury in vaccines played in the increasing rate of autism in this country.
Just last week, Congressman Burton wrote to the Special Masters in the U.S. Court of Federal Claims to share with them the DeSoto-Hitlan reanalysis of the Ip study. As the three special masters charged with adjudicating vaccine injury claims filed by parents of children with autism, Congressman Burton obviously believed it was important that they review this article as part of their deliberations. Why? – You might ask. In his own words:
I hope that you would agree with me that the Office of Special Masters has a duty and an obligation to review all sound science relevant to childhood vaccines, mercury, and autism. And, that's why I felt it so important to make the Office of Special Masters aware [of] this latest research.
As a Nation, I believe we have a collective responsibility to help the millions of children, adults and families afflicted with autism linked to a childhood vaccine. The Office of Special Masters is at the forefront of this battle.
(Read Congressman Burton's full letter at A-CHAMP's website - HERE)
If the courtroom is the only venue in our country where our children can even hope for answers, this is truly a sad state and we should hold all those who refuse to listen – listen without filters or deflectors – accountable. Self-imposed ignorance is no excuse. In this case, it violates every law of humanity.
Yes, Dr. Insel, there is a lot at stake.
Mary Webster is the mother of a son diagnosed with an autism spectrum disorder. She is a member of the board of directors of A-CHAMP and lives in Virginia.
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