Thirteen follies and fallacies about alternative medicine.

T use of alternative medicine (AM)—treatments such as herbs or massage therapy—has long been a part of healthcare in many regions of the world “to complement mainstream medicine by contributing to a common whole, by satisfying a demand not met by orthodoxy or by diversifying the conceptual frameworks of medicine” [1]. What AM cannot do is replace conventional treatment, particularly when it comes to serious or even life-threatening conditions. Nevertheless, many AM apologists insist that it can do so, that it is an alternative rather than a complement. This assumption can confuse patients and even endanger their lives. In this Opinion article, I explore some of the most common fallacies used to support, justify or promote AM. 1. Since many people believe in or practise AM, it is tempting to assume that it is useful. According to this argumentum ad populum, millions cannot all be wrong. However, belief can be wrong, practice can be misguided, and popularity is not a reliable indicator for effectiveness; after all, medicine is no popularity contest. The history of medicine is littered with examples that demonstrate how misleading this fallacy can be. Bloodletting was believed to be effective, was widely practised and highly popular, yet it certainly killed more patients than it ever helped. 2. The classic post hoc, ergo propter hoc fallacy—‘it worked for me (my aunt, my cat etc)’—is firmly engrained into the human mind. If a patient receives a treatment and then gets better, what could be more logical than to assume that the treatment was the cause of the improvement? This conclusion seems as obvious to patients—and many clinicians—as it is fallacious. Proponents of AM employ this fallacy incessantly to convince us that ineffective treatments are, in fact, effective. Apart from the treatment per se, a whole range of phenomena exists that can cause or contribute to improvement: the placebo effect, the natural history of the illness, the regression towards the mean and so on. It means that patients can get better after administering useless or even mildly harmful remedies; subsequently is not the same as consequently. Causal inferences based on anecdotes are therefore highly problematic and certainly no sound basis for robust conclusions about the efficacy of therapeutic interventions. Most apologists for AM argue that it is of secondary importance how a given type of AM works. Even if it were a pure placebo, they say, it would still help suffering patients through a placebo response, and surely that must be a good thing. In other words, the mechanism of the effect is of little practical relevance and what counts most is to help the patient. This fallacy ignores several important issues. The administration of placebos in clinical routine can be unethical and dangerous, but is also not necessary to produce a placebo response. If a clinician administers an effective therapy with empathy and compassion, he or she generates a placebo effect in addition to the specific therapeutic effect. Exclusively relying on placebos therefore deprives the patient of the latter. 3. Apologists for AM like to cite statistics that show how a sizeable percentage of all conventional treatments is not supported by sound evidence. Thus, they argue, it is unfair to insist on AM being solidly evidencebased. Unquestionably, many conventional therapies are currently not evidence-based. Yet, this is hardly a reasonable justification for using unproven or disproven forms of AM. Unreliable railways do not get more acceptable because thousands of people get stuck in traffic jams on the roads. 4. The adverse effects of conventional medicine are argued to be so serious and frequent that those of AM are negligible. While it is true that the risks of some conventional treatments are greater than those of some forms of AM, this is beside the point. The real value of a treatment is not determined by its absolute risk but by the balance between risk and benefit. If a treatment is potentially life-saving, substantial risks can be tolerated. If a therapy has no benefit, even a small risk would weigh heavily and the risk–benefit balance would not be positive. 5. Whenever scientific investigations fail to show what they had hoped for, apologists for AM claim that science cannot be meaningfully applied to their field. Their type of AM, they insist, is holistic, individualized, complex, relies on subtle, unquantifiable energies and so on, and these circumstances prevent it from being squeezed into the straight jacket of reductionist science. After all, there are many things “between heaven and earth” that science will never be able to capture. Science certainly has its limits. Yet, when it comes to testing therapeutic claims, it provides us with fairly adequate tools to assess them. Even if the claim is that a particular holistic, individualised and complex form of energy healing makes you feel better, live longer or experience life more wholesomely, the hypothesis is scientifically testable. Even if no validated outcome measure exists for a particular claim, scientists should be able to develop one. The notion that “a therapy defies scientific testing” merely discloses a lack of understanding of what science can achieve. Thirteen follies and fallacies about alternative medicine