Posts Tagged evidence-based medicine

The Forerunners of EBM

The term “evidence-based medicine” first appeared in the medical literature in 1992. It quickly became popular and developed into a systematic enterprise. A book by Ulrich Tröhler To Improve the Evidence of Medicine: The 18th century British origins of a critical approach argues that its roots go back to the 1700s in Scotland and England. An e-mail correspondent recommended it to me. Can’t remember who, but I would like to thank him.

Francis Bacon (1561-1626) differentiated between “ordinary experience” (chance observations) and more objective “ordered experience” (methodological observations). Both of these involved empirical knowledge.  It’s hard to get back into the mindset of his time, when most physicians rejected empiricism as the sphere of quacks and surgeons.  Tröhler helps us understand why they did:

…since antiquity, the mark of distinction of a learned man had been the certainty of his knowledge. A doctor knew — he did not need to test his kind of knowledge empirically because this would imply acknowledgement of uncertainty.


Posted in: Book & movie reviews, History

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“How do you feel about Evidence-Based Medicine?”

That was the question asked on a Medscape Connect discussion

I did a double-take. How do you feel? Could anybody object to the idea of basing treatments on evidence? The doctor who started the discussion asked:

Besides using EBM, a lot of my prescribing comes from anecdotal experience and intuition. How about you? Where do you get your information from that you use to treat your patients? Do you always ascribe to EBM, or do you deviate from it with certain medical conditions/patients?

I had naively thought that my profession uniformly embraced EBM. How could they not? The commenters broke my bubble big-time. Some of them summarily reject EBM… although it appears that what they are rejecting is not what I understand EBM to mean. (more…)

Posted in: Science and Medicine

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What is Science?

Consider these statements:

…there is an evidence base for biofield therapies. (citing the Cochrane Review of Touch Therapies)

The larger issue is what constitutes “pseudoscience” and what information is worthy of dissemination to the public. Should the data from our well conducted, rigorous, randomized controlled trial [of ‘biofield healing’] be dismissed because the mechanisms are unknown or because some scientists do not believe in the specific therapy?…Premature rejection of findings from rigorous randomized controlled trials are as big a threat to science as the continuation of falsehoods based on belief. Thus, as clinicians and scientists, our highest duty to patients should be to investigate promising solutions with high benefit/risk ratios, not to act as gatekeepers of information based on personal opinion.

–Jain et al, quoted here

Touch therapies may have a modest effect in pain relief. More studies on HT and Reiki in relieving pain are needed. More studies including children are also required to evaluate the effect of touch on children.

Touch Therapies are so-called as it is believed that the practitioners have touched the clients’ energy field.

It is believed this effect occurs by exerting energy to restore, energize, and balance the energy field disturbances using hands-on or hands-off techniques (Eden 1993). The underlying concept is that sickness and disease arise from imbalances in the vital energy field. However, the existence of the energy field of the human body has not been proven scientifically and thus the effect of such therapies, which are believed to exert an effect on one’s energy field, is controversial and lies in doubt.

—Cochrane Review of Touch Therapies, quoted here


Science is advanced by an open mind that seeks knowledge, while acknowledging its current limits. Science does not make assertions about what cannot be true, simply because evidence that it is true has not yet been generated. Science does not mistake absence of evidence for evidence of absence. Science itself is fluid.

—David Katz

When people became interested in alternative medicines, they asked me to help out at Harvard Medical School. I realized that in order to survive there, one had to become a scientist. So I became a scientist.

—Ted Kaptchuk, quoted here.

 …It seems that the decision concerning acceptance of evidence (either in medicine or religion) ultimately reflects the beliefs of the person that exist before all arguments and observation.

 —Ted Kaptchuk, quoted here.

Together they betray a misunderstanding of science that is common not only to “CAM” apologists, but to many academic medical researchers. Let me explain. (more…)

Posted in: Basic Science, Book & movie reviews, Clinical Trials, Energy Medicine, Faith Healing & Spirituality, Homeopathy, Medical Academia, Science and Medicine

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On the “individualization” of treatments in “alternative medicine,” revisited

As I contemplated what I’d like to write about for the first post of 2012, I happened to come across a post by former regular and now occasional SBM contributor Peter Lipson entitled Another crack at medical cranks. In it, Dr. Lipson discusses one characteristic that allows medical cranks and quacks to attract patients, namely the ability to make patients feel wanted, cared for, and, often, happy. As I (and several of us at SBM) have said before, it’s not necessary to invoke magic, quackery, or pseudoscience in order to show empathy to patients and provide them with the “human touch” that forges a strong therapeutic relationship between physician and patient and maximizes placebo effects without deception. In the old days, this used to be called “bedside manner,” but in these days of capitation and crappy third party payor reimbursement it’s very difficult for physicians to take the time necessary to listen to patients and thereby build the bonds of trust and mutual respect that can augment the treatments that are prescribed. Unfortunately, because of this the quacks have been all too eager to leap into the breach.

One aspect of this tendency of medical cranks is to claim that they somehow “individualize” their treatment to the patient, as Peter points out:

There are a number of so-called holistic doctors in town who claim to practice “individualized” medicine. What this really means isn’t clear. My colleagues and I certainly individualize the treatment plans for all of our patients, using data gleaned from decades of scientific studies of large groups of patients. What “individualized” care seems to mean in this other context is “stuff I made up to make that patient feel more unique and special.”


Posted in: Basic Science, Clinical Trials

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Dummy Medicine, Dummy Doctors, and a Dummy Degree, Part 2.2: Harvard Medical School and the Curious Case of Ted Kaptchuk, OMD (cont. again)

“Strong Medicine”: Ted Kaptchuk and the Powerful Placebo

At the beginning of the first edition of The Web that has no Weaver, published in 1983, author Ted Kaptchuk portended his eventual academic interest in the placebo:

A story is told in China about a peasant who had worked as a maintenance man in a newly established Western missionary hospital. When he retired to his remote home village, he took with him some hypodermic needles and lots of antibiotics. He put up a shingle, and whenever someone came to him with a fever, he injected the patient with the wonder drugs. A remarkable percentage of these people got well, despite the fact that this practitioner of Western medicine knew next to nothing about what he was doing. In the West today, much of what passes for Chinese medicine is not very different from the so-called Western medicine practiced by this Chinese peasant. Out of a complex medical system, only the bare essentials of acupuncture technique have reached the West. Patients often get well from such treatment because acupuncture, like Western antibiotics, is strong medicine.

Other than to wonder if Kaptchuk had watched too many cowboy ‘n’ Native American movies as a kid, when I first read that passage I barely blinked. Although the Chinese peasant may have occasionally treated someone infected with a bacterium susceptible to his antibiotic, most people will get well no matter what you do, because most illnesses are self-limited. Most people feel better even sooner if they think that someone with special expertise is taking care of them. If you want to call those phenomena the “placebo effect,” in the colloquial sense of the term, fine. That, I supposed, was what Kaptchuk meant by “strong medicine.”

Turns out I was mistaken. Let’s briefly follow Kaptchuk’s career path after 1983. In the 2000 edition of The Web, he wrote:


Posted in: Acupuncture, Basic Science, Book & movie reviews, Chiropractic, Clinical Trials, Homeopathy, Medical Academia, Science and Medicine

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Exorcism and Sorcery as Health Benefits?!

Luis Fernando Verissimo, a Brazilian writer, once proposed “voodoopuncture”. Instead of going to the acupuncturist, you would be treated without leaving home. The voodoopuncturist would stick acupuncture needles in the voodoo dolls of you! I add that voodoopuncture could be outsourced to Haiti and/or China. It is a win-win-win situation!

— Leonardo Monasteri, Brazilian economist

As unbelievable as this might sound, “voodoopuncture” is no fiction at all.

The practice is called “Tong Ren healing,” and involves needling or hammering an acupuncture mannequin, as if it were a voodoo doll. The main Tong Ren “Master” in the US is an acupuncturist in the Boston area by the name of Tom Tam. He treats groups of terminally ill and debilitated patients in a deliverance ceremony that is noting but a revamped Taoist exorcism — only the clay or straw doll is replaced by a plastic mannequin:

Unfortunately, Tom Tam is not the only licensed healthcare provider who is treating patients with hocus pocus and crackpottery. There are over 30,000 other adepts of Traditional Chinese Medicine (TCM) in the US who practice medicine based on notions of health and disease that are rooted in paranormal and magical beliefs. Some of these practitioners take their delusions to the outer limits of absurdity: consider, for instance, “acutonics” and “colorpuncture” as described in these videos:

In anthropology of religion, the principles that underline the above practices are called “imitation” (e.g. using a doll to affect a person), and “correspondence” (e.g. using a sound to affect an object). They are the hallmarks of what is called “sympathetic magic,” meaning the belief that a person, or a thing, can be affected through something that represents it, or that has similar attributes.1 The principle of magical correspondence in TCM is called wu xing (五行) in Chinese, and is known as the Five Phases/Elements Theory in English. It can be summarized as follows:

Posted in: Acupuncture, Politics and Regulation, Public Health

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Surprise, surprise! Dr. Andrew Weil doesn’t like evidence-based medicine

ResearchBlogging.orgDr. Andrew Weil is a rock star in the “complementary and alternative medicine” (CAM) and “integrative medicine” (IM) movement. Indeed, it can be persuasively argued that he is one of its founders, at least a founder of the its most modern iteration, and I am hard-pressed to think of anyone who did more in the early days of the CAM/IM movement, back before it ever managed to achieve a modicum of unearned respectability, to popularize CAM. In fact, no physician that I can think of has over the course of his lifetime done more to promote the rise of quackademic medicine than Dr. Weil. The only forces greater than Dr. Weil in promoting the infiltration of pseudoscience into academic medicine have been the Bravewell Collaborative and the National Center for Complementary and Alternative Medicine (NCCAM). Before there was Dr. Mehmet Oz, Dr. Dean Ornish, Dr. Mark Hyman, or any of the other promoters of IM, there was Dr. Weil.

And why not? Dr. Weil looks like an aging 1960s rock star, and, operating from his redoubt at the University of Arizona, is quite charismatic. For all the world he has the appearance of a kindly, benevolent Arizona desert Santa Claus, an ex-hippie turned respectable dispensing advice about “natural” medicines, writing books, and making himself ubiquitous on television and radio whenever the topic of alternative medicine comes up. Before Dr. Oz told Steve Novella that “Western” science and medicine can’t study woo like acupuncture, Dr. Weil was there, paving the way for such arguments, previously considered ludicrous, to achieve a patina of respectability.

In fact, he’s still at it, doing it far better and far more subtly than the ham-handed Dr. Oz. Unfortunately, it’s the same anti-science message and the same appeal to other ways of knowing built upon tearing down straw men versions of evidence-based medicine (EBM) with gusto. This was brought home last week when Dr. Weil co-authored an opinion piece with Drs. Scott Shannon and Bonnie J. Kaplan for the journal Alternative and Complementary Therapies entitled Safety and Patient Preferences, Not Just Effectiveness, Should Guide Medical Treatment Decisions, an article that was noted at the blog Booster Shots in a credulous, fawning post entitled Dr. Weil says there’s a better approach to evaluating clinical drug trials. In contast, Steve Novella put it far more succinctly (and accurately) in the title of his post: Andrew Weil Attacks EBM. That’s exactly what Weil and company did in this article.

While Steve is absolutely correct, I also see it more as Dr. Weil demonstrating once again that, upstarts like Dr. Oz aside, he is still the master of CAM/IM apologia, much as, even though both were Sith Lords, Emperor Palpatine remained master over Darth Vader until just before the end. You’ll see why in terms of the arguments, both subtle and not-so-subtle, that Dr. Weil and his acolytes make. Moreover, even though his disciple Shannon is granted the coveted first author position, the arguments presented leave little doubt that it’s Weil who’s driving the bus.

Posted in: Clinical Trials, Medical Academia

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CAM and Evidenced-Based Medicine

Mark Tonelli, MD has problems with evidence-based medicine (EBM). He has published a few articles detailing his issues, and he makes some legitimate points. We at science-based medicine (SBM) have a few issues with the execution of EBM as well, so I am sympathetic to constructive criticism.

In an article titled: Integrating evidence into clinical practice: an alternative to evidence-based approaches. The abstract states:

Evidence-based medicine (EBM) has thus far failed to adequately account for the appropriate incorporation of other potential warrants for medical decision making into clinical practice. In particular, EBM has struggled with the value and integration of other kinds of medical knowledge, such as those derived from clinical experience or based on pathophysiologic rationale. The general priority given to empirical evidence derived from clinical research in all EBM approaches is not epistemically tenable. A casuistic alternative to EBM approaches recognizes that five distinct topics, 1) empirical evidence, 2) experiential evidence, 3) pathophysiologic rationale, 4) patient goals and values, and 5) system features are potentially relevant to any clinical decision. No single topic has a general priority over any other and the relative importance of a topic will depend upon the circumstances of the particular case. The skilled clinician must weigh these potentially conflicting evidentiary and non-evidentiary warrants for action, employing both practical and theoretical reasoning, in order to arrive at the best choice for an individual patient.


Posted in: Science and Medicine

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Of SBM and EBM Redux. Part IV, Continued: More Cochrane and a little Bayes

OK, I admit that I pulled a fast one. I never finished the last post as promised, so here it is.

Cochrane Continued

In the last post I alluded to the 2006 Cochrane Laetrile review, the conclusion of which was:

This systematic review has clearly identified the need for randomised or controlled clinical trials assessing the effectiveness of Laetrile or amygdalin for cancer treatment.

I’d previously asserted that this conclusion “stand[s] the rationale for RCTs on its head,” because a rigorous, disconfirming case series had long ago put the matter to rest. Later I reported that Edzard Ernst, one of the Cochrane authors, had changed his mind, writing, “Would I argue for more Laetrile studies? NO.” That in itself is a reason for optimism, but Dr. Ernst is such an exception among “CAM” researchers that it almost seemed not to count.

Until recently, however, I’d only seen the abstract of the Cochrane Laetrile review. Now I’ve read the entire review, and there’s a very pleasant surprise in it (Professor Simon, take notice). In a section labeled “Feedback” is this letter from another Cochrane reviewer, which was apparently added in August of 2006, well before I voiced my own objections:


Posted in: Clinical Trials, Homeopathy, Medical Academia, Science and Medicine

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Of SBM and EBM Redux. Part IV: More Cochrane and a little Bayes

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.


Posted in: Clinical Trials, Energy Medicine, Faith Healing & Spirituality, Medical Academia, Medical Ethics, Science and Medicine

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