A question that arises often when discussing the optimal role of science in medicine is the precise role of plausibility, or prior probability. This is, in fact, the central concept that separates (for practical if not philosophical reasons) science-based medicine (SBM) from evidence-based medicine (EBM).
The concept featured prominently in the debate between myself and Dr. Katz at the recent Yale symposium that Kimball Atwood recently discussed. Dr. Katz’s treatment of the topic was fairly typical of CAM proponents, and consisted of a number of straw man derived from a false dichotomy, which I will describe in detail below.
I also recently received (I think by coincidence) the following question from an interested SBM reader:
What would Science Based Medicine do if H. pylori was not known, but a study showed that antibiotics given to patients with stomach ulcers eliminated symptoms? I assume that SBM wouldn’t dismiss it outright saying that it couldn’t possibly be helping because antibiotics don’t reduce stomach acid. I assume a SBM approach would do further studies trying to discover why antibiotics work. But, in the meantime, would a SBM practitioner refuse to give antibiotics to patients because he doesn’t have a scientific explanation as to why it works?
This is the exact type of scenario raised by David Katz during our discussion. He claimed that strict adherence to the principles of SBM would deprive patients of effective treatments, simply because we did not understand how they work. This is a pernicious straw man that significantly misconstrues the nature of plausibility and its relationship to the practice of medicine.
The Main Event: Novella vs. Katz
The remainder of the Symposium comprised two panels. The first was what I had come to see: a Moderated Discussion on Evidence and Plausibility in the Context of CAM Research and Clinical Practice, featuring our Founder, Steve Novella, who is also Assistant Professor of Neurology at Yale; and David Katz, the speaker who had borne the brunt of the criticism after the 2008 conference (as I wrote in Part I). According to the Symposium syllabus, he is:
David L. Katz, MD, MPH, FACPM, FACP, an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care. He is a board certified specialist in both Internal Medicine, and Preventive Medicine/Public Health, and Associate Professor (adjunct) in Public Health Practice at the Yale University School of Medicine. Katz is the Director and founder (1998) of Yale University’s Prevention Research Center; Director and founder of the Integrative Medicine Center at Griffin Hospital (2000) in Derby, CT; founder and president of the non-profit Turn the Tide Foundation; and formerly the Director of Medical Studies in Public Health at the Yale School of Medicine for eight years. He currently serves as Chair of the Connecticut Chapter of the Partnership to Fight Chronic Disease and represents Yale University on the Steering Committee of the Consortium of Academic Health Centers for Integrative Medicine.
The syllabus had excerpted that statement from a much larger, remarkable document, which I urge you to review.
I will attempt to report the Moderated Discussion as neutrally as possible, as though I were a disinterested journalist (don’t worry: later I’ll rail).
One (dark and stormy?) night in 1882, a critically ill 70 year old woman was at the verge of death at her daughter’s home, suffering from fever, crippling pain, nausea, and an inflamed abdominal mass. At 2 AM, a courageous surgeon put her on the kitchen table and performed the first known operation to remove gallstones. The patient recovered uneventfully. The patient was the surgeon’s own mother.
This compelling story is the beginning of an excellent new biography of William Halsted, the father of modern surgery, Genius on the Edge: The Bizarre Double Life of Dr. William Stewart Halsted, by Gerald Imber, MD.
When Halsted went to medical school, surgeons still operated in street clothes, with bare hands, and major surgical procedures carried a mortality rate of nearly 50 percent. Suppuration of wounds was called laudable pus. Lister had recently introduced carbolic acid dips and sprays (that were irritating and toxic), but hand washing was discouraged because it was thought to force germs into skin crevices. (more…)
I get all sorts of mail. I get mail from whining Scientologists, suffering patients, angry quacks—and I get lots of promotional material. I get letters from publishers wanting me to review books, letters from pseudo-bloggers wanting me to plug their advertiblog—really, just about anything you can imagine.
Most of the time I just hit “delete”; it’s obvious that they’ve never read my blog and they’re just casting a wide net for some link love. But a recent email from a PR firm piqued my interest: (it’s a long letter, and I won’t be offended if you simply reference it rather than read the whole thing now):
A few months ago, I wrote about a particularly nasty form of cancer quackery known as the “German New Medicine” or Die Germanische Neue Medizin in German. As you may recall, the German New Medicine is based on the nonsensical idea that cancer arises from an internal emotional conflict. This conflict then results in what is called the “Dirk Hamer Syndrome” (DHS) or “Dirk Hamer focus” in the brain, named after Dr. Ryke Geerd Hamer‘s son Dirk, who was tragically shot in his sleep by Vittorio Emanuel, the last crown prince of Italy. After a prolonged course requiring multiple operations, Dirk succumbed to his wounds and died. Three years later, Dr. Hamer developed testicular cancer, and, in a perfect case of post hoc ergo propter hoc, Hamer decided that it was the psychic shock of his son’s death that had caused his cancer. Thus was born Die Germanische Neue Medizin, which, according to Hamer, promises a 95% or more chance of curing any cancer, no matter how advanced. Never mind that Hamer apparently underwent a combination of surgery and other “conventional therapies for his testicular cancer. Also never mind that these “Dirk Hamer Focus” to which Hamer pointed on CT scans of the brain appeared, more than anything else, to be artifacts of the imaging process and nothing real.
As I described in my previous post in October, the German New Medicine is a seriously dangerous form of cancer quackery that is not only worthless but in many cases blames the patient for having developed cancer. Evidence can be found in this video, where a proponent of German New Medicine gives as examples of psychic stress a “cancer blow” that comes from menopause, in which loss of estrogen supposedly leads women to feel that they “aren’t the woman they used to be” and that that conflict is manifest in the bone or an athlete’s anger because of an injury that screws up his ability to perform leading to an osteosarcoma of extremity.
Unfortunately, cancer quackery frequently evolves under the selective pressure of competition with other cancer quackeries and based on the unique environments in which various forms of quackery come to land. Since I first wrote my post about Die Germanische Neue Medizin, I’ve been meaning to address one of its offshoots. The particular offshoot that I plan to address is, in essence, the French cousin of Die Germanische Neue Medizin, and it’s called Biologie Totale, or Total Biology (Claude Sabbah’s official site is here, but it’s all in French). I first became aware of Biologie Totale about a year and a half ago through this news story:
March 4, 2010
Today I went to the one-day, 2nd Yale Research Symposium on Complementary and Integrative Medicine. Many of you will recall that the first version of this conference occurred in April, 2008. According to Yale’s Continuing Medical Education website, the first conference “featured presentations from experts in CAM/IM from Yale and other leading medical institutions and drew national and international attention.” That is true: some of the national attention can be reviewed here, here, here, and here; the international attention is here. (Sorry about the flippancy; it was irresistible)
I’ve not been to a conference promising similar content since about 2001, and in general I’ve no particular wish to do so. This one was different: Steve Novella, in his day job a Yale neurologist, had been invited to be part of a Moderated Discussion on Evidence and Plausibility in the Context of CAM Research and Clinical Practice. This was not to be missed.
Children aren’t supposed to die. That so many of us accept this statement without a blink is remarkable and wonderful, but it is also a very recent development in human history. Modern sanitation, adequate nutrition, and vaccination have largely banished most of the leading killers of children to the history books. Just look at the current leading causes of childhood death in developing countries to see how far these relatively simple interventions have taken us.
As we have systematically removed the leading infectious killers of children from prominence, other organisms have naturally risen to the top of the list. This has lead some to the fatalistic (and mistaken) conclusion that we are simply opening up niches to be inevitably filled by other virulent organisms. This assumes that there is some mandated quota of say, meningitis, that children must suffer every year, and if one organism doesn’t meet this quota then another will fill it. Were this the case, after vaccination we’d expect to see a shift in the causes of meningitis, but at best a transient drop in the total number of cases per year as other bugs step in to pick up the slack of their fallen, virulent, meningitis-inducing brethren. Such is not the case.
Though new organisms are now the leading causes of invasive bacterial infections in children, and we have indeed seen some increases in non-vaccine targeted strains, as I’ll discuss below, the total number of such infections has dropped precipitously. It’s fair to say that the vaccination program has done a remarkable job improving a child’s chance of surviving to adulthood in good health. However, no one in their right mind would argue that the current state of affairs, as good as it is, is good enough, and so we have shifted our sights to the current leading cause of invasive bacterial infections in children, Streptococcus pneumoniae (S. pneumo, or pneumococcus). (more…)
I just thought I’d make a brief announcement that I’m currently in St. Louis attending the annual meeting of the Society of Surgical Oncology. If any of our St. Louis readers are attending the meeting, look me up. I’d be tickled to death to know whether any of my colleagues here are even aware of SBM, much less regular readers. (If no one is aware, though, I’ll be disappointed.) Heck, if you show me your mad skillz at writing and that you share our philosophy, maybe you can even join us as another blogger here!
Also, if anyone’s interested in attempting a meetup, let me know. I’ll be in St. Louis until Sunday morning. It may or may not be possible, given that the SSO meeting fills each day quite nicely and most evenings have something booked, including meeting up with a former postdoc of mine who happens to be at Washington University now, but you never know until you ask. Unfortunately, Saturday night probably out, unless it’s before 7 PM or after 10 PM. My mentor, Dr. Mitch Posner, is the incoming president of the SSO; so I want to go to the Presidential Banquet that evening.
I spent 43 years in private practice as a “science-based” chiropractor and a critic of the chiropractic vertebral subluxation theory. I am often asked how I justified practicing as a chiropractor while renouncing the basic tenets of chiropractic. My answer has always been: I was able to offer manipulation in combination with physical therapy modalities as a treatment for mechanical-type back pain—a service that was not readily available in physiotherapy or in any other sub-specialty of medicine.
If I had it to do over again, however, I would study physical therapy rather than chiropractic. Considering the controversy that continues to surround the practice of chiropractic, I would not recommend that anyone spend the time, effort, and money required to earn a degree in chiropractic. Physical therapy, which is now beginning to include spinal manipulation in its treatment armamentarium, may offer better opportunity for those interested in manual therapy. Properly-limited, science-based chiropractors are now essentially competing with physical therapists who use manual therapy. Unfortunately, only a few chiropractors have renounced the vertebral subluxation theory, making it difficult to find a “good chiropractor.” I consider physical therapy to be more progressive and more evidence based. For this reason, I generally recommend the manipulative services of a physical therapist rather than a chiropractor.
There are some science-based chiropractors who use manipulation appropriately, but until the chiropractic profession abandons the implausible vertebral subluxation theory and is defined according to standards dictated by anatomy, physiology, and neurology, I would not describe it as a science-based profession.
One of the basic principles of science-based medicine is that a single study rarely tells us much about any complex topic. Reliable conclusions are derived from an assessment of basic science (i.e prior probability or plausibility) and a pattern of effects across multiple clinical trials. However the mainstream media generally report each study as if it is a breakthrough or the definitive answer to the question at hand. If the many e-mails I receive asking me about such studies are representative, the general public takes a similar approach, perhaps due in part to the media coverage.
I generally do not plan to report on each study that comes out as that would be an endless and ultimately pointless exercise. But occasionally focusing on a specific study is educational, especially if that study is garnering a significant amount of media attention. And so I turn my attention this week to a recent study looking at acupuncture in major depression during pregnancy. The study concludes:
The short acupuncture protocol demonstrated symptom reduction and a response rate comparable to those observed in standard depression treatments of similar length and could be a viable treatment option for depression during pregnancy.