The fundamental concept of science-based medicine (SBM) is that medical practice should be based upon the best available science. This may seem obvious, but there are many important details to its application, such as the relationship between clinical and basic science. Clinical claims require clinical evidence, but clinical evidence can be tricky and is often preliminary. It is therefore helpful (I would say essential) to view the clinical evidence in light of all of the rest of science.
A thorough basic and clinical science analysis of a medical claim can be summarized by the term “plausibility,” or “prior probability” if you want to put it into statistical terms. When we say a certain belief is plausible we mean it is consistent with what we know from the rest of science. In other words, because of the many weaknesses of clinical evidence, in order for a therapy to be generally accepted as part of SBM it should have a certain minimal supporting clinical evidence and overall scientific plausibility.
These can exist in different proportions – for example one therapy may be highly plausible (it would be shocking if it were not true) and have modest supporting clinical evidence, while another may have unknown plausibility but with solid clinical evidence of efficacy. But no therapy should have clinical evidence that suggests lack of efficacy, nor extreme implausibility (not just an unknown mechanism, but no possible mechanism).
During the early days of the 2009 H1N1 influenza A pandemic, the popular herbal formula maxingshigan–yinqiaosan was used widely by TCM practitioners to reduce symptoms. (It’s hard to pronounce and spell, so I’ll refer to it as M-Y.) A new study was done to test whether M-Y worked and to compare it to the prescription drug oseltamivir. It showed that M-Y did not work for the purpose it was being used for: it did not reduce symptoms, although it did reduce the duration of one sign, fever, allowing researchers to claim they had proved that it works as well as oseltamivir.
“Oseltamivir Compared With the Chinese Traditional Therapy: Maxingshigan–Yinqiaosan in the Treatment of H1N1 Influenza” by Wang et al. was published in the Annals of Internal Medicine earlier this month. The study was done in China, which is notorious for only publishing positive studies. Even if it were an impeccable study, we would have to wonder if other studies with unfavorable results had been “file-drawered.” It’s not impeccable; it’s seriously peccable.
It was randomized, prospective, and controlled; but not placebo controlled, because they couldn’t figure out how to prepare an adequate placebo control. They considered that including a no treatment group compensated for not using a placebo control, and that objective temperature measurement could be expected to get around any bias. It might not: the nurses who took the temperatures were blinded to the study, but the patients were not. It’s possible that those who knew they were getting M-Y might have believed in it and their bias might have somehow subtly influenced data gathering so that M-Y appeared more equivalent to oseltamivir than it actually was.
There are other problems besides the lack of blinding. (more…)
Detroit is my hometown, and three and a half years ago, after nearly twenty years away wandering between residency, graduate school, fellowship, and my first academic job, I found myself back in Detroit minted as surgical faculty at Wayne State University and practicing and doing research at the Barbara Ann Karmanos Cancer Institute. One thing that I had forgotten about while I was away for so many years is just how intimately southeast Michigan interacts with Canada. This closeness is not surprising, given that Detroit and Windsor are separated by only about a half mile of Detroit River. Indeed, a there are a lot of Canadians who cross the border on a daily basis to work in the Detroit area, many of them in the medical center within which my cancer center is located. The reason I point this out is not to wax nostalgic for trips to Windsor or for the occasional trip to Stratford to see plays but to point out that Ontario is right next to us. What happens there is of concern to me because I know quite a few people who live there and because it can on occasion influence what goes on over here on the U.S. side of the border.
I recently learned that the College of Physicians and Surgeons of Ontario (CPSO) has been working on updating its policy on the use of nonconventional medical therapies. The wag in me can’t help but wonder why such a policy would need to say anything other than that, if it isn’t science- and evidence-based, the CPSO doesn’t support using it, but in a less sarcastic moment I realized that such a policy is probably not that bad an idea, as long as it doesn’t legitimize pseudoscience, which is, of course, the biggest pitfall to be avoided when writing such a policy. Not too long ago, the CPSO released its draft policy and has asked for public comments, with the deadline being September 1. I was happy to learn that I had not missed the deadline, because there is much to comment about regarding this policy, but it’s definitely true that time’s short. Unfortunately, I wasn’t so happy when I read the title of the draft policy, namely Non-Allopathic (Non-Conventional) Therapies in Medical Practice, with a subtitle of “Formerly named Complementary Medicine.” The full policy in PDF form can be found at this link.
The recent albuterol vs. placebo trial reported in the New England Journal of Medicine (NEJM) found that experimental subjects with asthma experienced substantial, measured improvements in lung function after inhaling albuterol, but not after inhaling placebo, undergoing sham acupuncture, or “no treatment.” It also found that the same subjects reported having felt substantially improved after either albuterol or each of the two sham treatments, but not after “no treatment.” Anthropologist Daniel Moerman, in an accompanying editorial, wrote, “the authors conclude that the patient reports were ‘unreliable,’ since they reported improvement when there was none”—precisely as any rational clinician or biomedical scientist would have concluded.
In Part 1 of this blog we saw that Moerman took issue with that conclusion. He argued, with just a bit of hedging, that the subjects’ perceptions of improvement were more important than objective measures of their lung function. I wondered how the NEJM editors had chosen someone whose bibliography predicted such an anti-medical opinion. I doubted that Editor-in-Chief Jeffrey Drazen, an expert in the pathophysiology of asthma, had ever heard of Moerman. I suggested, in a way that probably appeared facetious, that Ted Kaptchuk, the senior author of the asthma report, might have recommended him. (more…)
Acupuncture, Chiropractic, Clinical Trials, Health Fraud, Herbs & Supplements, History, Medical Academia, Medical Ethics, Naturopathy, Pharmaceuticals, Science and Medicine, Science and the Media
Online discussions on the merits of alternative medicine can get quite heated. And its proponents, given enough time, will inevitably cite the same drug as “evidence” of the failings of science. Call it Gavura’s Law, with apologies to Mike Godwin:
As an online discussion on the effectiveness of alternative medicine grows longer, the probability that thalidomide will be cited approaches one.
A recent comment on my own blog, regarding the homeopathic product Traumeel, is typical:
If the scientific method is all that separates an accepted claim, ie Thalidomide, Vioxx, Bextra, Darvon, from mere anecdote, of what benefit is the Science?
As a non-scientist consumer, I’ll take the anecdotes and my own experience. Thank you.
If scientists want to be taken seriously, they must stop selling themselves to the highest bidder becoming corporate whores without a shred of decency. To my mind, that’s how the claims for Thalidomide, Vioxx, Bextra, Darvon were accepted, making the scientific method utterly worthless.
To this commenter, “science has been wrong before.” And that invalidates science, and apparently validates homeopathy. It’s a fallacious argument. But does thalidomide actually represent a failing of science-based medicine? No, not even close. It’s so wrong, it’s not even wrong. Thalidomide is good example of the importance of science-based medicine and why allowing alternative medicine to be sold in the absence of good science is a concern. (more…)
There have been many cases now of big companies or organizations, or wealthy individuals, threatening to sue or actually suing a blogger for libel. The most famous case is that of Simon Singh who was sued by the British Chiropractic Association over comments he made in an article. Simon braved through the expensive and exhaustive legal process (which is especially onerous in England), but he is not just a lone blogger. He is a successful author and was writing for the Guardian. Eventually the BCA was forced to drop the case – but only after the blogging community rallied behind Simon, magnifying his criticisms of the BCA by orders of magnitude. By all accounts it was a PR disaster.
The blogging community as a whole is rather passionate about this issue. We exist on the premise of free and open public discourse about important issues. At SBM we take on many controversial issues and we don’t pull our punches when criticizing what we see as pseudoscience in medicine. So of course we take notice when a large company tries to bully a blogger to silence their legitimate criticism.
According to the BMJ this has happened yet again – this time the international homeopathy producer, Boiron, is threatening a lone Italian blogger because he dared to criticize their product, Oscillococcinum. The blogger, Samuele Riva, wrote two articles on his blog, blogzero.it, criticizing what our own Mark Crislip has called “oh-so-silly-coccinum.” The blog is entirely in Italian, but he is maintaining a page in English with updates on the Boiron vs Blogzero affair.
Common warts (verruca vulgaris) are more of a nuisance than a serious health problem, but they are interesting. There is a whole mythology surrounding their cause (touching toads?) and treatment (everything from banana peels to vitamin C). Many people believe they can be made to vanish by suggestion or hypnosis. I used to believe that too.
Every doctor has wart stories. Here are some of mine.
- A patient made an appointment to see me because he had a wart, but when he tried to show me his wart he discovered that it had vanished! Apparently, just making the appointment cured it.
- Another patient did have obvious warts and I prescribed the “wart medicine” that our pharmacy tech compounded, based on salicylic acid. He was out of one of the ingredients and had to ask my patient to return in a week. When she returned, her warts were already gone. The wart medicine apparently worked so well that you didn’t even have to use it!
- I worked with a dermatologist who used a colorful laminated card with a picture of a toad to stroke children’s warts, telling them it was a wart remover. In his experience, this would frequently make the wart vanish over the next few days. Was this ethical? Was he lying and deliberately deceiving patients, or could this be excused as playing make-believe to distract the child and improve his attitude about the wart?
Author’s note: This post was inspired in part by a post by Wally Sampson entitled Why would medical schools associate with quackery? Or, How we did it.
Once upon a time, there was quackery.
Long ago, back in the mists of time before many of our current readers were even born and far back in the memory of even our wizened elders of medicine, “quackery” was the preferred term used to refer to ineffective and potentially harmful medical practices not supported by evidence. Physicians, having a grounding in science and prior plausibility, for the most part understood that modalities such as homeopathy, reflexology, and various “energy healing” (i.e., faith healing) methodologies were based either on prescientific vitalism, magical thinking, and/or science that was at best incorrect or at the very least grossly distorted. More importantly, physicians weren’t afraid to call quackery quackery, quacks quacks, and charlatans charlatans.
Not surprisingly, quacks and charlatans did not like this.
Summertime and the living is busy. Finally we have sun in the Northwest. While the rest of the country has been melting in heat, this year we have rarely cracked 85. Global heating has avoided Oregon this year, and I will need some green tomato recipes. Good weather, work is busy, and it is the last two weeks with my eldest before he is off to Syracuse, so there is little time for writing, so a brief entry this week.
I always wince at the way anything can be called ‘therapy.’ We have music therapy and garden therapy and pet therapy and art therapy. I do not deny that it is beneficial for people to participate in those activities while in the hospital, although I am never happy to see disease vectors, er, animals in a hospital. Dinner should be food therapy, reading should be book therapy, and using the internet should be computer therapy. I guess it is like calling something ‘medical’ grade, and you can bill more for it.
Some ‘therapies’ are a wee bit more odd. Indonesians are using railroad therapy. People lie down on electric railroad tracks because “the electricity current from the track could cure various diseases.” To date no one has been either electrocuted or squashed, but I suppose it is only a matter of time.
I have as much of a sense of nostalgia as anyone. I love history. I think that there is lots to be said about the “good old days,” whenever the heck they were. I do not, however, think that the “good old days” generally include medicine.
The fact is that it’s only been about 100 or so years since medical practitioners really got their acts together and started to be able to figure out if they were actually doing anything good. Prior to that, medicine was a world of humo(u)rs and miasms, treated by bleeding, burning, and purging, plants and animal matter of all sorts (the 6th century Chinese apparently liked otter feces) and all sorts of other awfulness. In light of some of the things that were done, it’s kind of amazing that anyone survived their treatments. Mostly, people (and horses) survived in spite of the crazy things that were done to them.
Nevertheless, in those wild and wooly days of yesteryear, enterprising medical entrepreneurs turned out an endless stream of products, with some pretty fantastic claims. They designed some absolutely artistic advertising cards to go along with those claims, too. These trade cards surged onto the scene in the 1870’s, coinciding with the advent of color printing.