Complementary and alternative medicine (CAM) is popular, and many nurses seem to be embracing it in the hope of helping their patients, as recent publications in JAN show (Chang et al. 2012, Zhang et al. 2012, Charalambous et al. 2014, Close et al. 2014, Ernst 2014, Hökkä et al. 2014). But despite its popularity, CAM has remained a highly controversial area: the evidence-base is often unconvincing or non-existent. For most forms of CAM, we thus know too little to claim with confidence that they generate more good than harm (Ernst et al. 2006). In the interest of our patients, it might, therefore, be wise to exercise caution and be aware of some of the fallacies which can easily mislead us.
Because of CAM's widespread usage (Hunt & Ernst 2005), it is tempting to assume that thousands of people cannot be mistaken in assuming that CAM is effective. However, the appeal to belief or popularity is a classic fallacy. Beliefs can be wrong and popularity is certainly not a reliable indicator for effectiveness. Health care is no popularity contest and must be judged by different criteria. The history of medicine is littered with examples which demonstrate how misleading this fallacy can be. For instance, bloodletting was believed to be effective, widely practised and highly popular – yet it has killed more patients than it ever helped.
If a patient enjoys a particular form of CAM and subsequently feels better, what could be more logical than to assume that the treatment was the cause of our improvement? This conclusion seems obvious to most patients and nurses alike – yet it is fallacious. Apart from the treatment per se, a whole range of phenomena can cause or at least contribute to a clinical improvement in a sick patient: the placebo-effect, the natural history of the illness, the regression towards the mean, etc. In other words, patients can improve after administering useless or even mildly harmful remedies; and the word ‘subsequently’ has not the same meaning as ‘consequently’. Causal inferences based on anecdotes are highly problematic and rarely a sound basis for robust conclusions about the effectiveness of therapeutic interventions.
Enthusiasts claim that most forms of CAM have stood the ‘test of time’ and that this test is more relevant than that of a clinical trial. A long tradition of use can, of course, be an indicator for the safety and efficacy of a treatment, but it can never be a proof. On the contrary, a long history might also mean that the origins of that therapy reach back to a time when our understanding of anatomy, physiology etc. was in its infancy. This in turn, might lessen the chances for any such intervention to be plausible or effective. Ancient treatments such as bloodletting or purging again provide apt examples.
An entire industry has developed around the notion that CAM is natural and, therefore, safe. The implication is that conventional treatments are unnatural, heavily based on chemicals which are potentially harmful. Nature, by contrast, is seen as benign and natural remedies are therefore to be preferred. This argument is as effective for marketing purposes as it is wrong. First, by no means are all forms of CAM natural. For instance, there is nothing natural in sticking needles into a patient's body (as in acupuncture) or endlessly diluting and shaking a medicine (as in homoeopathy). Second, nature is not necessarily benign. Even ‘natural’ herbal extracts are not necessarily safe (Ernst et al. 2006) – just think of hemlock.
In the realm of CAM, fallacious thinking seems to abound. It has the potential to misguide us all into making therapeutic decisions which are not in the best interest of their patients. With all the enthusiasm that currently exists in favour of CAM, we must not forget our obligation to adhere to the principles of evidence-based medicine and critical evaluation. Only for very few forms of CAM is there currently sound evidence of effectiveness and safety. Where such evidence is missing, we should endeavour to conduct more research. Where the evidence is negative, we should think twice before being seduced by fallacious arguments.