I emerge from the haze of board exams and residency interviews to blog about a recent development on campus that disappointed me, involving a university celebration of Black History Month. (more…)
Archive for Medical Academia
NB: This is a partial posting; I was up all night ‘on-call’ and too tired to continue. I’ll post the rest of the essay later…
This is the fourth and final part of a series-within-a-series* inspired by statistician Steve Simon. Professor Simon had challenged the view, held by several bloggers here at SBM, that Evidence-Based Medicine (EBM) has been mostly inadequate to the task of reaching definitive conclusions about highly implausible medical claims. In Part I, I reiterated a fundamental problem with EBM, reflected in its Levels of Evidence scheme, that although it correctly recognizes basic science and other pre-clinical evidence as insufficient bases for introducing novel treatments into practice, it fails to acknowledge that they are necessary bases. I explained the difference between “plausibility” and “knowing the mechanism.”
I showed, with several examples, that in the EBM lexicon the word “evidence” refers almost exclusively to the results of clinical trials: thus, when faced with equivocal or no clinical trials of some highly implausible claim, EBM practitioners typically declare that there is “not enough evidence” to either accept or reject the claim, and call for more trials—although in many cases there is abundant evidence, other than clinical trials, that conclusively refutes the claim. I rejected Prof. Simon’s assertion that we at SBM want to “give (EBM) a new label,” making the point that we only want it to live up to its current label by considering all the evidence. I doubted Prof. Simon’s contention that “people within EBM (are) working both formally and informally to replace the rigid hierarchy with something that places each research study in context.”
In Part II I responded to the widely held assertion, also held by Prof. Simon, that there is “societal value in testing (highly implausible) therapies that are in wide use.” I made it clear that I don’t oppose simple tests of basic claims, such as the Emily Rosa experiment, but I noted that EBM reviewers, including those employed by the Cochrane Collaboration, typically ignore such tests. I wrote that I oppose large efficacy trials and public funding of such trials. I argued that the popularity gambit has resulted in human subjects being exposed to dangerous and unethical trials, and I quoted language from ethics treatises specifically contradicting the assertion that popularity justifies such trials. Finally, I showed that the alleged popularity of most “CAM” methods—as irrelevant as it may be to the question of human studies ethics—has been greatly exaggerated.
All the world sees us
In grand style wherever we are;
The big and the small
Are infatuated with us:
They run to our remedies
And regard us as gods
And to our prescriptions
Principles and regimens, they submit themselves.
Molière, The Imaginary Invalid (1673)1
The passage above is part of a burlesque doctoral conferment ceremony, where the French playwright Molière (1622-1673) mocks the unscrupulous physicians of his time. “All the excellency of their art consists in pompous gibberish, in a specious babbling, which gives you words instead of reasons, and promises instead of results,” he writes. In Moliere’s plays doctors never cure anyone; they are put on stage just to display their own vanity and ignorance.2 The Spanish painter Francisco de Goya (1746-1828) also took on the same issue by painting in 1799 a well attired jackass taking the pulse of a dying man, in a pose that accentuates the large gem on his hoof.
But if the asinine doctors of Molière and de Goya’s time never cured anyone, it is because they held prescientific views, and believed that disease was caused by imbalances in “humors,” and by malefic influences of the Heavens. Even the most educated among them treated illnesses in good faith by purging, bloodletting and enema at astrologically auspicious times. In contrast, current physicians who for the sake of funding embrace and endorse unscientific views and practices under the guise of CAM or integrative medicine, do so knowing that they often contradict the established principles of physics, chemistry, and biology. Therefore, in addition to promoting “snake oil science”3 (as R. Barker Bausell calls it), these physicians are also guilty of bad faith. Most of this takes place at large academic centers, where funding seems to outweigh the concern for science. As Val Jones, MD, writes in 2009′s Top 5 Threats To Science In Medicine:
Often referred to by David Gorski as “Quackademic” Medical Centers – there is a growing trend among these centers to accept endowments for “integrative” approaches to medical care. Because of the economic realities of decreasing healthcare reimbursements – these once proud defenders of science are now accepting money to “study” implausible and often disproven medical treatments because they’re trendy. Scientists at these centers are forced to look the other way while patients (who trust the center’s reputation that took tens of decades to build) are exposed to placebo medicine under the guise of “holistic” healthcare.
This is the third post in this series*; please see Part II for a review. Part II offered several arguments against the assertion that it is a good idea to perform efficacy trials of medical claims that have been refuted by basic science or by other, pre-trial evidence. This post will add to those arguments, continuing to identify the inadequacies of the tools of Evidence-Based Medicine (EBM) as applied to such claims.
Prof. Simon Replies
Prior to the posting of Part II, statistician Steve Simon, whose views had been the impetus for this series, posted another article on his blog, responding to Part I of this series. He agreed with some of what both Dr. Gorski and I had written:
The blog post by Dr. Atwood points out a critical distinction between “biologically implausible” and “no known mechanism of action” and I must concede this point. There are certain therapies in CAM that take the claim of biological plausibility to an extreme. It’s not as if those therapies are just implausible. It is that those therapies must posit a mechanism that “would necessarily violate scientific principles that rest on far more solid ground than any number of equivocal, bias-and-error-prone clinical trials could hope to overturn.” Examples of such therapies are homeopathy, energy medicine, chiropractic subluxations, craniosacral rhythms, and coffee enemas.
The Science Based Medicine site would argue that randomized trials for these therapies are never justified. And it bothers Dr. Atwood when a systematic review from the Cochrane Collaboration states that no conclusions can be drawn about homeopathy as a treatment for asthma because of a lack of evidence from well conducted clinical trials. There’s plenty of evidence from basic physics and chemistry that can allow you to draw strong conclusions about whether homeopathy is an effective treatment for asthma. So the Cochrane Collaboration is ignoring this evidence, and worse still, is implicitly (and sometimes explicitly) calling for more research in this area.
On the other hand:
There are a host of issues worth discussing here, but let me limit myself for now to one very basic issue. Is any research justified for a therapy like homeopathy when basic physics and chemistry will provide more than enough evidence by itself to suggest that such research is futile(?) Worse still, the randomized trial is subject to numerous biases that can lead to erroneous conclusions.
I disagree for a variety of reasons.
Let us be certain of a fact before being concerned with its cause. It is true that this method is too lengthy for most people who naturally run to the cause and overlook the certitude about facts; but at last we will avoid the ridicule of finding the cause of what does not exist.1
Bernard le Bovier de Fontenelle (1657-1757)
Amidst the plethora of flawed, implausible, and wasteful research on acupuncture and Chinese medicine, a 2002 study on the “Relationship of Acupuncture Points and Meridians to Connective Tissue Planes” stands out as the height of factual neglect. In it, Helene Langevin and Jason Yandow of the University of Vermont’s College of Medicine claim to have matched real anatomical structures with the elusive acupuncture “meridians.” It should be noted that the widely accepted term “meridian” is a metaphor coined by George Soulié de Morant (1878 – 1955), a French delegate to China, and has no semantic relationship with the original Chinese word.2 The original designation is the composite word jing luo (經絡), which literally means “channel-network.” The term has been translated to English as chinglo channels, channels, vessels or more commonly, meridians. Debunking this study is of particular relevance because it is often used by acupuncturists and a wide range of other CAM providers to legitimize the meridian lore. The principle author, Helene Langevin, is a CAM celebrity and a member of the “Scientific Committee” of the International Fascia Research Congress, an organization dedicated to the “emerging field of Fascia Studies.” She is an Associate Professor of Neurology and the Director of the Program in Integrative Health at the University of Vermont; and has conducted multiple NCCAM-funded studies on the role of connective tissue in chronic pain, acupuncture and manual therapies.
This is the second post in a series* prompted by an essay by statistician Stephen Simon, who argued that Evidence-Based Medicine (EBM) is not lacking in the ways that we at Science-Based Medicine have argued. David Gorski responded here, and Prof. Simon responded to Dr. Gorski here. Between that response and the comments following Dr. Gorski’s post it became clear to me that a new round of discussion would be worth the effort.
Part I of this series provided ample evidence for EBM’s “scientific blind spot”: the EBM Levels of Evidence scheme and EBM’s most conspicuous exponents consistently fail to consider all of the evidence relevant to efficacy claims, choosing instead to rely almost exclusively on randomized, controlled trials (RCTs). The several quoted Cochrane abstracts, regarding homeopathy and Laetrile, suggest that in the EBM lexicon, “evidence” and “RCTs” are almost synonymous. Yet basic science or preliminary clinical studies provide evidence sufficient to refute some health claims (e.g., homeopathy and Laetrile), particularly those emanating from the social movement known by the euphemism “CAM.”
It’s remarkable to consider just how unremarkable that last sentence ought to be. EBM’s founders understood the proper role of the rigorous clinical trial: to be the final arbiter of any claim that had already demonstrated promise by all other criteria—basic science, animal studies, legitimate case series, small controlled trials, “expert opinion,” whatever (but not inexpert opinion). EBM’s founders knew that such pieces of evidence, promising though they may be, are insufficient because they “routinely lead to false positive conclusions about efficacy.” They must have assumed, even if they felt no need to articulate it, that claims lacking such promise were not part of the discussion. Nevertheless, the obvious point was somehow lost in the subsequent formalization of EBM methods, and seems to have been entirely forgotten just when it ought to have resurfaced: during the conception of the Center for Evidence-Based Medicine’s Introduction to Evidence-Based Complementary Medicine.
Thus, in 2000, the American Heart Journal (AHJ) could publish an unchallenged editorial arguing that Na2EDTA chelation “therapy” could not be ruled out as efficacious for atherosclerotic cardiovascular disease because it hadn’t yet been subjected to any large RCTs—never mind that there had been several small ones, and abundant additional evidence from basic science, case studies, and legal documents, all demonstrating that the treatment is both useless and dangerous. The well-powered RCT had somehow been transformed, for practical purposes, from the final arbiter of efficacy to the only arbiter. If preliminary evidence was no longer to have practical consequences, why bother with it at all? This was surely an example of what Prof. Simon calls “Poorly Implemented Evidence Based Medicine,” but one that was also implemented by the very EBM experts who ought to have recognized the fallacy.
There will be more evidence for these assertions as we proceed, but the main thrust of Part II is to begin to respond to this statement from Prof. Simon: “There is some societal value in testing therapies that are in wide use, even though there is no scientifically valid reason to believe that those therapies work.”
During the most recent kerfuffle about whether or not Evidence-Based Medicine can legitimately claim to be science-based medicine, it became clear to me that a whole, new round of discussion and documentation is necessary. This is frustrating because I’ve already done it several times, most recently less than a year ago. Moreover, I’ve provided a table of links to the whole series at the bottom of each post*…Never mind, here goes, and I hope this will be the last time it is necessary because I’ll try to make this the “go to” series of posts for any future such confusions.
The points made in this series, most of which link to posts in which I originally made them, are in response to arguments from statistician Steve Simon, whose essay, Is there something better than Evidence Based Medicine out there?, was the topic of Dr. Gorski’s rebuttal on Monday of this week, and also from several of the comments following that rebuttal. Mr. Simon has since revised his original essay to an extent, which I’ll take into account. I’ll frame this as a series of assertions by those who doubt that EBM is deficient in the ways that we at SBM have argued, followed in each case by my response.
First, a disclaimer: I don’t mean to gang up on Mr. Simon personally; others hold opinions similar to his, but his essay just happens to be a convenient starting point for this discussion. FWIW, prior to this week I perused a bit of his blog, after having read one of his comments here, and found it to be well written and informative.
Attacks on science-based medicine (SBM) come in many forms. There are the loony forms that we see daily from the anti-vaccine movement, quackery promoters like Mike Adams and Joe Mercola, those who engage in “quackademic medicine,” and postmodernists who view science as “just another narrative,” as valid as any other or even view science- and evidence-based medicine as “microfascism.” Sometimes, these complaints come from self-proclaimed champions of evidence-based medicine (EBM) who, their self-characterization otherwise, show signs of having a bit of a soft spot for the ol’ woo. Then sometimes there are thoughtful, serious criticisms of some of the assumptions that underlie SBM.
The criticism I am about to address tries to be one of these but ultimately fails because it attacks a straw man version of SBM.
True, the criticism of SBM I’m about to address does come from someone named Steve Simon, who vocally supports EBM but doesn’t like the the criticism of EBM implicit in the very creation of the concept of SBM. Simon has even written a very good deconstruction of postmodern attacks on evidence-based medicine (EBM) himself, as well as quite a few other good discussions of medicine and statistics. Unfortunately, in his criticism, Simon appears to have completely missed the point about the difference between SBM and EBM. As a result, his criticisms of SBM wind up being mostly the application of a flamethrower to a Burning Man-sized straw man representing what he thinks SBM to be. It makes for a fun fireworks show but is ultimately misdirected, a lot of heat but little light. For a bit of background, Simon’s post first piqued my curiosity because of its title, Is there something better than Evidence Based Medicine out there? The other reason that it caught my attention was the extreme naiveté revealed in the arguments used. In fact, Simon’s naiveté reminds me very much of my very own naiveté about three years ago.
Here’s the point where I tell you a secret about the very creation of this blog. Shortly after Steve Novella invited me to join, the founding members of SBM engaged in several e-mail frank and free-wheeling exchanges about what the blog should be like, what topics we wanted to cover, and what our philosophy should be. One of these exchanges was about the very nature of SBM and how it is distinguished from EBM, the latter of which I viewed as the best way to practice medicine. During that exchange, I made arguments that, in retrospect, were eerily similar to the ones by Simon that I’m about to address right now. Oh, how epic these arguments were! In retrospect, I can but shake my head at my own extreme naiveté, which I now see mirrored in Simon’s criticism of SBM. Yes, I was converted, so to speak (if you’ll forgive the religious terminology), which is why I see in Simon’s article a lot of my former self, at least in terms of how I used to view evidence in medicine.
The main gist of Simon’s complaint comes right at the beginning of his article:
A couple of weeks ago, in a review of the Mayo Clinic Book of Home Remedies, Harriet Hall expressed relief that she hadn’t found any “questionable recommendations for complementary & alternative medicine (CAM) treatments” in that book:
Since “quackademic” medicine is infiltrating our best institutions and organizations, I wasn’t sure I could trust even the prestigious Mayo Clinic.
The Home Remedies book may be free of woo, but Dr. Hall was right to wonder if she could trust the Mayo Clinic. About a year ago I was asked to comment on an article in the American Journal of Hematology (AJH), in which investigators from the Mayo Clinic reported that among a cohort of lymphoma patients who were “CAM” users,
There was a general lack of knowledge about forms of CAM, and about potential risks associated with specific types of CAM…
This suggests the need to improve access to evidence-based information regarding CAM to all patients with lymphoma.
The Mayo Clinic Book of Alternative Medicine details dozens of natural therapies that have worked safely for many patients in treating 20 top health issues. You may be surprised that Mayo Clinic now urges you and your doctor to consider yoga, garlic, acupuncture, dietary supplements and other natural therapies. Yet the record is clear. Many of these alternative therapies can help you achieve reduced arthritis pain, healthier coronary arteries, improved diabetes management, better memory function and more.
Nor could such a paradox be explained by the right hand not having known what the left was doing: Brent Bauer, MD, the Director of the Mayo Clinic Complementary and Integrative Medicine Program, is both the medical editor of the Book of Alternative Medicine (MCBAM) and a co-author of the article in the AJH.
As chance would have it, I had picked up a copy of the latest (2011) edition of the MCBAM only a couple of days before Dr. Hall’s post. Does it live up to its promises? Do its “straight answers from the world’s leading medical experts” respond to “the need to improve access to evidence-based information regarding CAM?” Let’s find out. In some cases I’ll state the implied questions and provide the straight answers.
Bloodletting, of course, was a major aim of early vessel therapy and is frequently described in the Su wen.1
Paul U Unschuld
“Cargo cult” is a metaphor that describes the act of imitating an activity or a practice without any insight into the underlying principles. In the literal sense, it refers to a magico-religious practice observed in tribal societies, where the members ritually imitate the activities of a technologically-advanced society they had contact with, so that they can magically draw their material wealth. For instance, after WWII, indigenous tribes in New Guinea who had come in close contact with cargo planes, started to build landing strips and populated them with plane-like effigies that were made of straw, bamboo, and coconuts, so that they can magically lure the passing planes.2 The term “cargo cult science” was introduced by Richard Feynman in a speech at Caltech in 1974 to describe pseudoscientific studies in which all the superficial aspects of a scientific inquiry are adhered to, but the underlying principles are not scientific. He classified many educational and psychological studies as such, for having the appearance of academic research but lacking the principles of a scientific inquiry.3
Another example of cargo cult science is the plethora of two-arm acupuncture studies that compare a needling regimen using the traditional concepts, and compare it with a non-interventional placebo. These studies might have the appearance of clinical research, but they are inherently flawed and inconclusive, because they do not rule out the possibility that the observed results are mainly due to the painful stimulus and injury caused by a needle, which can occur regardless of the insertion point. Indeed, an acute noxious stimulus from a prickle, heat, or any other painful stimulus – almost anywhere on the skin – can attenuate the perception of pain in another area of the body through a reflex called “counter-irritation,” also called the “pain-inhibiting-pain effect” or “diffuse noxious inhibitory control” (DNIC).4 DNIC was extensively studied by Fauve et al. in the 1980s, who showed in mice that it has an effect equivalent or superior to that of glucocorticoids.5,6