Short Attention Span SBM

The bar on this blog is set high. The entries are often complete, with no turn left unstoned. Yet, not every topic needs the full monty with every post. The blog has extensive evaluations on many topics, and new medical literature doesn’t require another complete analysis. Many new articles add incrementally to the literature and their conclusions need to be inserted into the conversation of this blog, like a car sliding into heavy traffic. My eldest son just received his driver’s license, and car metaphors are on my mind. As are crash metaphors and insurance metaphors.

So in response to this need, a need only recognized by me, I give you Short Attention Span SCAM. Occasionally I will summarize a few recent studies and their key points as they relate to prior posts at SBM.


Posted in: Acupuncture, Herbs & Supplements, Science and Medicine, Vaccines

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Christiane Northrup: more bad medicine

A question popped up on facebook the other day about Dr. Christiane Northrup, an OB/GYN who has been a frequent guest on Oprah.  I hadn’t heard much about her for a while, but a foul taste still lingered from previous encounters with her work.  So I went over to her website to see what fare she’s currently dishing up.  It isn’t pretty. (Cached version).

This month’s news item is titled “Angst Over Not Vaccinating Children is Unwarranted.” Regular readers will be expecting a typical antivax screed, and they won’t be disappointed, but I’d like to highlight some of the propaganda techniques Northrup uses to advance her dangerous lies.

She begins her story with this:

In June, 2010 there was an outbreak of pertussis (whooping cough) in California that reporters were calling the worst epidemic in 50 years.

There are two problems with this opening sentence.  The outbreak is ongoing, and it’s not “reporters” who are calling it “the worst epidemic in 50 years.”  The California Department of Public Health reports that the state has seen the largest number of cases in the last 55 years.  Of course the state was much smaller 55 years ago, so for comparison they give us an incidence rate: 10.3 cases/100,000 in 2010, the highest rate in 48 years (when the rate was 10.9 cases/100,000).  So far in California, there have been 9 deaths.  All of the deaths were in babies eight of whom were unvaccinated and one of whom had been vaccinated only days before becoming ill, not early enough to develop immunity.

Posted in: Science and Medicine

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CFLs, Dirty Electricity and Bad Science

Governments and environmental advocates are promoting compact fluorescent lightbulbs (CFLs) as a way of reducing electricity use, saving money, and reducing our carbon footprint. CFLs are not a perfect technology – when turned on they take a moment to fully brighten and they contain a small amount of mercury which requires special procedures for disposal. CFLs are likely also to be a transitional technology, as more energy efficient light sources (such as LEDs) are already coming onto the market.  But CFLs are a safe and energy efficient alternative to incandescent bulbs.

It seems, however, with any new technology comes a wave of internet fearmongering, and CFLs are now a prime target. YouTube videos are circulating claiming that CFLs cause headaches, mercury toxicity, a host of symptoms from electromagnetic sensitivity, and something called “type 3 diabetes.”  Let’s take a look at the claims and the science.

Mercury in CFLs

There is a small amount of mercury in each CFL, necessary for the function of the bulb, about 4mg on average, with some newer bulbs having as little as 1.4mg. There is no exposure to mercury from using CFLs, as long as they are not broken. Even if a bulb is broken the exposure to mercury is negligible, far less than eating a tuna fish sandwich. But still, there are recommended procedures for cleaning up and disposing of a broken bulb to further minimize exposure, such as not using a vacuum, and ventilating the area. These procedures represent the cautionary principle in action, but make it easy to fearmonger about the risks of the mercury in the bulb.


Posted in: Public Health, Science and Medicine

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How not to consult your biostatistician before doing an experiment

A friend of mine at work sent this video to me in great amusement.

I just hope he wasn’t making a comment on my behavior when it comes to dealing with our biostatisticians. I have, of course, seen investigators approach biostatistians this late in the game. Not that I’ve ever flirted with this sort of behavior, of course. At least the researcher in the video above actually consulted the biostatistician before doing the experiment, rather than after doing an experiment with inadequate statistical power to answer the question asked. On the other hand, I guess it doesn’t matter if the researcher doesn’t listen, does it?

Posted in: Humor, Science and Medicine

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PTSD Breakthrough?: It’s Not Science Just Because Someone Says So

It infuriates me when someone misappropriates the word “science” to promote treatments that are not actually based on science. I have just read a book entitled The PTSD Breakthrough: The Revolutionary Science-Based Compass Reset Program by Dr. Frank Lawlis, a psychologist who is the chief content advisor for Dr Phil and The Doctors. There is very little science in the book and references are not provided. It amounts to an indiscriminate catalog of everything Dr. Lawlis can imagine that might help post-traumatic stress disorder (PTSD) patients.  (more…)

Posted in: Book & movie reviews, Neuroscience/Mental Health

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Clinical equipoise versus scientific rigor in cancer clinical trials

A critical aspect of both evidence-based medicine (EBM) and science-based medicine (SBM) is the randomized clinical trial. Ideally, particularly for conditions with a large subjective component in symptomatology, the trial should be randomized, double-blind, and placebo-controlled. As Kimball Atwood pointed out just last week, in EBM, scientific prior probability tends to be discounted while in SBM it is not, particularly for therapies that are wildly improbable strictly on the basis of basic science, but for both the randomized clinical trial remains, in essence, where the “rubber hits the road,” so to speak. Indeed, when the prior probability of a therapy working based on preclinical basic science investigations appears high, EBM and SBM should be (and are, for the most part) more or less indistinguishable.

The ethics of clinical trials, however, demand a characteristic known as clinical equipoise. Stated briefly, for purposes of clinical trials, clinical equipoise demands that at the time a clinical trial is being carried out there be a state of genuine scientific uncertainty in the medical community over which of the drugs or treatments being tested is more efficacious and safer. One reason (among many) why the Gonzalez trial was completely unethical was a lack of clinical equipose. (Lack of adequate informed consent was another.) Lack of clinical equipoise is also the reason why a prospective randomized, double-blind, placebo-controlled clinical trial testing an unvaccinated group versus a vaccinated control group to determine whether vaccines cause autism would be completely unethical. Such a trial would egregiously violate the principle of clinical equipoise because the unvaccinated group would be left unprotected against potentially life-threatening vaccine-preventable diseases, and that is completely unacceptable from an ethical perspective. Consequently, we have had to rely on on the accumulation of data from less rigorous trial designs to demonstrate that there is no correlation between vaccines and autism. Even so, the accumulated weight of such evidence is enough, and for some questions that is the best we can do because scientific rigor sometimes conflicts with human subjects research ethics. This is an extreme example of lack of clinical equipoise, but it illustrates the point. If we know (or have good scientific reason to suspect) that one treatment is better than another, it is unethical to randomize patients to the arm that receives what is, based on what is known at the time of the trial, likely to be an inferior treatment.

Sometimes, however, the question of whether clinical equipoise exists in a clinical trial is not so obvious as it is for trials proposed by cranks. This situation sometimes crops up in clinical trials for cancer. I was reminded of this issue by a front page story in the New York Times yesterday, New Drugs Stir Debate on Basic Rules of Clinical Trials. In it, reporter Amy Harmon uses a classic human interest story to highlight the issue of clinical equipoise in a clinical trial for a new drug for melanoma that shows great promise. In brief, it is the story of two cousins, one of whom is receiving the new “wonder drug” (whether it is truly a wonder drug or not remains to be seen) in a clinical trial and one of whom is receiving the current standard of care for stage IV melanoma, which, to put it bluntly, sucks in that it has very little effect in prolonging life:

Posted in: Cancer, Clinical Trials, Medical Ethics

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Evidence-Based Medicine, Human Studies Ethics, and the ‘Gonzalez Regimen’: a Disappointing Editorial in the Journal of Clinical Oncology Part 2

NB: If you haven’t yet read Part 1 of this blog, please do so now; Part 2 will not summarize it.

At the end of Part 1, I wrote:

We do not need formal statistics or a new, randomized trial with a larger sample size to justify dismissing the Gonzalez regimen.

In his editorial for the JCO, Mark Levine made a different argument:

Can it be concluded that [the] study proves that enzyme therapy is markedly inferior? On the basis of the study design, my answer is no. It is not possible to make a silk purse out of a sow’s ear.

That conclusion may be correct in the EBM sense, but it misses the crucial point of why the trial was (ostensibly) done: to determine, once and for all, whether there was anything to the near-miraculous claims that proponents had made for a highly implausible “detoxification” regimen for cancer of the pancreas. Gonzalez himself had admitted at the trial’s inception that nothing short of an outcome matching the hype would do:

DR. GONZALEZ: It’s set up as a survival study. We’re looking at survival.

SPEAKER: Do you have an idea of what you’re looking for?

DR. GONZALEZ: Well, Jeff [Jeffrey White, the director of the Office of Cancer Complementary and Alternative Medicine at the NCI—KA] and I were just talking a couple weeks ago. You know, to get any kind of data that would be beyond criticism is—-always be criticism, but at least three times.

You would want in the successful group to be three times — the median to be three times out from the lesser successful groups.

So, for example, if the average survival with chemo, which we suspect will be 5 months, you would want my therapy to be at least — the median survival to be at least 15, 16, 17 months, as it was in the pilot study.

We’re looking for a median survival three times out from the chemo group to be significant.

Recall that the median survival in the Gonzalez arm eventually turned out to be 4.3 months.


Posted in: Cancer, Clinical Trials, Health Fraud, Medical Academia, Medical Ethics, Politics and Regulation, Science and Medicine

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Using attacks on science by the anti-vaccine movement as a “teachable moment”

Last week, I wrote one of my usual ridiculously detailed posts analyzing a recent study (Price et al) that, if science and reason ruled, would be the last nail in the coffin of the hypothesis connecting autism with the mercury-containing preservative, thimerosal, which used to be in many childhood vaccines but was phased out beginning in 1999 and disappearing in infant vaccines except for the flu vaccine by early 2002. Of course, for at least the last five years, the thimerosal-autism hypothesis has been a notion whose coffin already had so many nails pounded into it that Price et al probably had a hard time finding even a tiny area of virgin wood into which to pound even a tiny nail of a study published in an impact factor one journal, much less the spike that their study in Pediatrics represented.

Unfortunately, as we know, in the anti-vaccine movement unreason rules, and, not unexpectedly, as a result this study has changed little in the debate, the fortuitously ironic happenstance of its being released the day before Mark Blaxill and Dan Olmsted’s anti-mercury screed Age of Autism not withstanding. To physicians and scientists, it is another strong piece of data being added to the confluence of evidence that has shown no link between mercury in vaccines and autism (or vaccines themselves and autism, for that matter). It is yet another confirmation that vaccines are safe. In contrast, to the anti-vaccine movement, it is simply yet another confirmation that the CDC is hopelessly biased, that scientists are in on a conspiracy to suppress The Truth, and that they are the poor persecuted minority, the only ones who know What Is Really Going On.

When I wrote my post last week, I didn’t know whether or not it would be worth my while to comment on the response of anti-vaccine activists to the study. The reason is that, as fun as it is to reveal their responses to be as vacuous as they are, I wasn’t sure that it would be educational. Granted, sometimes educational value takes a back seat to criticism, but sometimes it’s just too easy. In any case, by mid-week, there had been virtually no criticism of the study yet from the usual sources; so I figured it to be a moot point whether or not I would end up writing about this study one last time. Then, on Thursday morning I noted an e-mail in my in box. In order to keep my finger on the pulse of various pseudoscience movements, I subscribe to e-mail lists of various crank organizations, one of which is Generation Rescue and another of which is SafeMinds. SafeMinds, as you may recall, is the organization headed up by Sallie Bernard. As you may also recall, Bernard was originally on the external consulting committee that participated in the design of Price et al, and, before it, Thompson et al, the two of which ultimately made up a one-two punch against the mercury-autism hypothesis. When she saw that the results of Thompson et al were going against her idea and that no link between thimerosal-containing vaccines and neurodevelopmental disorders was showing up in the preliminary analyses, she resigned from the committee and started attacking Thompson et al. What surprised me was that she wasn’t ready with a criticism of Price et al when it was released.

Posted in: Clinical Trials, Vaccines

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Evidence-Based Medicine, Human Studies Ethics, and the ‘Gonzalez Regimen’: a Disappointing Editorial in the Journal of Clinical Oncology Part 1

Background: the distinction between EBM and SBM

An important theme on the Science-Based Medicine blog, and the very reason for its name, has been its emphasis on examining all the evidence—not merely the results of clinical trials—for various claims, particularly for those that are implausible. We’ve discussed the distinction between Science-Based Medicine (SBM) and the more limited Evidence-Based Medicine (EBM) several times, for example here (I began my own discussion here and added a bit of formality here, here, and here). Let me summarize by quoting John Ioannidis:

…the probability that a research finding is indeed true depends on the prior probability of it being true (before doing the study), the statistical power of the study, and the level of statistical significance.

EBM, in a nutshell, ignores prior probability† (unless there is no other available evidence) and falls for the “p-value fallacy”; SBM does not. Please don’t bicker about this if you haven’t read the links above and some of their own references, particularly the EBM Levels of Evidence scheme and two articles by Steven Goodman (here and here). Also, note that it is not necessary to agree with Ioannidis that “most published research findings are false” to agree with his assertion, quoted above, about what determines the probability that a research finding is true.

The distinction between SBM and EBM has important implications for medical practice ethics, research ethics, human subject protections, allocation of scarce resources, epistemology in health care, public perceptions of medical knowledge and of the health professions, and more. EBM, as practiced in the 20 years of its formal existence, is poorly equipped to evaluate implausible claims because it fails to acknowledge that even if scientific plausibility is not sufficient to establish the validity of a new treatment, it is necessary for doing so.

Thus, in their recent foray into applying the tools of EBM to implausible health claims, government and academic investigators have made at least two, serious mistakes: first, they have subjected unwary subjects to dangerous but unnecessary trials in a quest for “evidence,” failing to realize that definitive evidence already exists; second, they have been largely incapable of pronouncing ineffective methods ineffective. At best, even after conducting predictably disconfirming trials of vanishingly unlikely claims, they have declared such methods merely “unproven,” almost always urging “further research.” That may be the proper EBM response, but it is a far cry from the reality. As I opined a couple of years ago, the founders of the EBM movement apparently “never saw ‘CAM’ coming.”


Posted in: Cancer, Clinical Trials, Medical Academia, Medical Ethics, Politics and Regulation, Science and Medicine

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Aspartame – Truth vs Fiction

If you believe everything you read on the internet, then is seems that a chemical found in thousands of products is causing an epidemic of severe neurological and systemic diseases, like multiple sclerosis and lupus. The FDA, the companies that make the product, and the “medical industrial complex” all know about the dangers of this chemical but are hiding the truth from the public in order to protect corporate profits and avoid the pesky paper work that would accompany the truth being revealed. The only glimmer of hope is a dedicated band of bloggers and anonymous e-mail chain letter authors who aren’t afraid to speak the truth. Armed with the latest anecdotal evidence, unverified speculation, and scientifically implausible claims, they have been tirelessly ranting about the evils of this chemical for years. Undeterred by the countless published studies manufactured by the food cartel that show this chemical is safe, they continue to protect the public by spreading baseless fear and hysteria.

Hopefully, you don’t believe everything you read on the internet, and you don’t get your science news from e-mail SPAM, where the above scenario is a common theme. While there are many manifestations of this type of urban legend, I am speaking specifically about aspartame – an artificial sweetener used since the early 1980s. The notion that aspartame is unsafe has been circulating almost since it first appeared, and like rumors and misinformation have a tendency to do, fears surrounding aspartame have taken on a life of their own.

I am frequently asked my opinion about the safety of aspartame. Nutritionists often council to avoid the sweetener, citing unverified claims that it is unsafe. I was recently sent a chain letter warning that aspartame causes MS (which of course can be cured by simply avoiding aspartame), and Snopes informs me that this particular letter first appeared in 1998.


Posted in: Public Health

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