The Difference Between Science-Based Medicine And "Complementary And Alternative Medicine" (CAM)
Cancer surgeon David Gorski writes at Science Based Medicine:

"Alternative medicine," so-called "complementary and alternative medicine" (CAM), or, as it's become fashionable to call it, "integrative medicine" is a set of medical practices that are far more based on belief than science. As Mark Crislip so pointedly reminded us last week, CAM is far more akin to religion than science-based medicine (SBM). However, as I've discussed more times than I can remember over the years, both here and at my not-so-super-secret-other blog, CAM practitioners and advocates, despite practicing what is in reality mostly pseudoscience-based medicine, crave the imprimatur that science can provide, the respect that science has had. That is why, no matter how scientifically implausible the treatment, CAM practitioners try to tart it up with science. I say "tart it up" because they aren't really providing a scientific basis for their favored quackery. In reality, what they are doing is choosing science-y words and using them as explanations without actually demonstrating that these words have anything to do with how their favored CAM works.

...A more important fundamental difference between CAM and real medicine is that CAM practices are not rejected based on evidence. Basically, they never go away. Take homeopathy, for example. (Please!) It's the ultimate chameleon. Even 160 years ago, it was obvious from a scientific point of view that homeopathy was nonsense and that diluting something doesn't make it stronger. When it became undeniable that this was the case, through the power of actually knowing Avogadro's number, homeopaths were undeterred. They concocted amazing explanations of how homeopathy "works" by claiming that water has "memory." It supposedly "remembers" the substances with which it's been in contact and transmits that "information" to the patient. No one's ever been able to explain to me why transmitting the "information" from a supposed memory of water is better than the information from the real drug or substance itself, but that's just my old, nasty, dogmatic, reductionistic, scientific nature being old, nasty, dogmatic, reductionistic, and scientific. Then, of course, there's the term "quantum," which has been so widely abused by Deepak Chopra, his acolytes, and the CAM community in general, while the new CAM buzzword these days to explain why quackery "works" is epigenetics. Basically, whenever a proponent of alternative medicine uses the word "epigenetics" or "quantum" to explain why an alternative medicine treatment "works," what he really means is, "It's magic."

...So, yes, "conventional" medicine doesn't always get it right. Occasionally it gets it wrong, on rare occasions spectacularly wrong. But unlike most CAM modalities EBM/SBM is self-correcting. It actually does abandon treatments that don't work. The process might be messy and ugly at times, but it does happen. For example, many years ago, angina pectoris was sometimes treated with a surgical procedure known as mammary artery ligation. The idea was that tying off these arteries would divert more blood to the heart. The operation became popular on the basis of relatively small, uncontrolled case series. Then, two randomized, sham surgery-controlled clinical trials were published in 1959 and 1960. Both of these trials showed no difference between bilateral internal mammary artery ligation and sham surgery. Very rapidly, surgeons stopped doing this operation. A similar example is one I mentioned above: bone marrow transplantation for advanced breast cancer, which was similarly rapidly abandoned after randomized clinical trials showing it to be no better than the previous standard of care. I'm not saying that this happened without conflict or disagreement; proponents of these therapies can always find reasons to discount the clinical trial evidence. But in the end evidence and science do win out.

Now compare this to CAM practices. Can anyone name a CAM treatment that was abandoned by CAM practitioners as a result of research and randomized clinical trials showing that it doesn't work? A single one? I can't. That's the difference between CAM and EBM/SBM. The day that I see a CAM practice go extinct, like bilateral internal mammary artery ligation for angina pectoris, is the day that I might start to take seriously CAM practitioner claims that they are science-based.