Jan 09 2012
If there’s one thing I’ve learned over the past seven years or so that I’ve been blogging, first at my other “super secret” (or, more accurately, super “not-so-secret”) blogging location, and then the four years I’ve been blogging here at Science-Based Medicine (SBM), it’s that the vast majority of “alternative medicine,” “complementary and alternative medicine” (CAM), and “integrative medicine” (IM) treatments (or whatever you want to call them) are nothing more than placebo medicine. True, there are exceptions, such as herbal treatments, mainly because they can contain chemicals in them that are active drugs, but any critical look at things like homeopathy (which is water), reiki (which is faith healing substituting Eastern mystical beliefs for Christianity), acupuncture (whose effects, when tested rigorously, are found to be nonspecific), or “energy healing” must conclude that any effects these modalities have are placebo effects or responses. Given writings on this topic by Steve Novella, Mark Crislip, Harriet Hall, Peter Lipson, myself, and others, this should be abundantly clear to readers of this blog, but, even so, it bears repeating. In fact, it probably can’t be repeated enough.
There was a time not so long ago when proponents of unscientific medicine tried very, very hard to argue that their nostrums have real effects on symptoms and disease above and beyond placebo effects. They would usually base such arguments on small, less rigorously designed clinical trials, mainly because, if there’s another thing I knew before from my medical education but that has been particularly reinforced in me since I started blogging, it’s that small clinical trials are very prone to false positives. Often they’d come up with some handwaving physiological or biological explanation, which, in the case of something like homeopathy, often violated the laws of chemistry and physics. Be that as it may, the larger and more rigorously designed the clinical trial, the less apparent effects become until, in the case of CAM therapies that do nothing (like homeopathy), they collapse into no effect detectable above that of placebo. Even so, there are often enough apparently “positive” clinical trials of water (homeopathy) that homeopaths can still cling to them as evidence that homeopathy works. Personally, I think that Kimball Atwood put it better when he cited a homeopath who said bluntly, “Either homeopathy works, or clinical trials don’t!” and concluded that, for highly implausible treatments like homeopathy, clinical trials as currently constituted under the paradigm of evidence-based, as opposed to science-based, medicine don’t work very well. Indeed, contrasting SBM with EBM has been a major theme of this blog over the last four years. In any case, for a long time, CAM enthusiasts argued that CAM really, really works, that it does better than placebo, just like real medicine.
Over the last few years, however, some CAM practitioners and quackademics have started to recognize that, no, when tested in rigorous clinical trials their nostrums really don’t have any detectable effects above and beyond that of placebo. A real scientist, when faced with such resoundingly negative results, would abandon such therapies as, by definition, a placebo therapy is a therapy that doesn’t do anything for the disease or condition being treated. CAM “scientists,” on the other hand, do not abandon therapies that have been demonstrated not to work. Instead, some of them have found a way to keep using such therapies. The way they justify that is to argue that placebo medicine is not just useful medicine but “powerful” medicine. Indeed, an article by Henry K. Beecher from 1955 referred to the “powerful placebo.” This construct allows them then to “rebrand” CAM unashamedly as “harnessing the power of placebo” as a way of defending its usefulness and relevance. In doing so, they like to ascribe magical powers to placebos, implying that placebos can do more than just decrease the perception of pain or other subjective symptoms but in fact can lead to objective improvements in a whole host of diseases and conditions. Some even go so far as to claim that there can be placebo effects without deception, citing a paper in which the investigators — you guessed it! — used deception to convince their patients that their placebos would relieve their symptoms. Increasingly, placebos are invoked as a means of “harnessing the power of the mind” over the body in order to relieve symptoms and cure disease in what at times seems like a magical mystery tour of the brain.
Part of what allows CAM practitioners to get away with this is that placebo effects are poorly understood even by most physicians and, not surprisingly, even more poorly understood by the public. Moreover, we all like to think that we have more control than we do over our bodies and, in particular, illnesses and symptoms, which is why the selling of placebo effects as a means of harnessing some innate hidden power we have to control our own bodies through the power of mind is so attractive to so many, including some scientists and physicians. Exhibit A is Ted Kaptchuk, the researcher from Harvard University responsible for spinning an interesting study of placebo effects in asthma into the invocation of the power of placebo. Kimball Atwood has written extensively about Kaptchuk recently, revealing his rather dubious background and arguments. More recently, however, Kaptchuk seems to be everywhere, appearing in articles and interviews, promoting just the argument I’m talking about, that CAM is a way of harnessing placebo effects, so much so that I felt it was time to take a look at this argument.