Evidence And Complementary Therapy by Jane Thurnell-Read

Whether they call it complementary therapy, alternative medicine or CAM, the opponents all say the same thing – there is a lack of evidence that it works.

Anecdotal evidence is generally dismissed as insignificant, even though anecdotal evidence features in many medical journals, but there it’s called ‘Case Studies’ which makes the evidence sound much more impressive.

Even if the huge number of case studies of the efficacy of CAM is accepted, opponents often say that, because CAM does not fit in with our current scientific understanding of the universe, the need for evidence is greater than for conventional medicine techniques and therapies. Scientists admit they only have any real understanding of about 4% of the universe and even then that is far from complete. The rest is dark matter and dark energy that have never been directly observed, but are inferred from their effects – changes in gravitational pull and the rate of expansion of the universe, so the fact that they don’t understand how CAM could possibly work fits in with all the rest of the universe that they do not understand.

Even so critics will say: Extraordinary claims require extraordinary evidence. This phrase was popularised by Carl Sagan, professor of astronomy, Cornell University.  If I said I had just bought a pink dress, you would probably believe me without needing to see the dress. If I said I had just bought a pink dress with purple spots designed by Armani, you would probably be more sceptical, but would accept the statement if I could produce a photograph of myself in such a dress (although with the advent of Photoshop and similar software this might now not be sufficient).  If I said I had just bought a dress made out of seal skin with ivory buttons, you would probably not believe me unless you saw the dress (particularly as you know I am a vegetarian); my word or a photograph would not be sufficient as the claim is so extraordinary.

Similarly critics argue that the claims of alternative medicine are so extraordinary – how can homeopaths claim that sugar pills can make dramatic changes when their clients take it? How can kinesiologists say that they can ‘talk to the body’ through muscle testing? These are extraordinary claims that need extraordinary evidence.

When scientists and others use the phrase about extraordinary evidence they imply that they are being objective and rational, but the phrase itself implies that a judgement has already been made – that a given claim is extraordinary.

Another example shows this perhaps more clearly. Which is the more extraordinary claim: ‘I have been cured of cancer by a homeopath’ or ‘I have been cured of cancer by God’? In assessing these alternative claims I am swayed by factors outside of the claims. If I am a devout Catholic, I may well think that the God claim is the more likely. If I have experience of homeopathy curing me of arthritis, I may well think the homeopathic cure is the more likely. For someone like Richard Dawkin (an atheist and, judging by his TV series, a critic of alternative medicine) both claims would probably seem equally extraordinary and he would want to use terms accepted by mainstream medicine such as ‘spontaneous remission’. In judging the complexity or extraordinariness of the claims our views about the world and our experiences of it influence how we assess these rival claims.

Precisely because scientists believe CAM is extraordinary they demand more rigorous evidence, but tucked away within that is a value judgement of huge proportions.

This does not mean that  evidence for the efficacy of CAM is not needed. It is needed, but scientists have to ask themselves how much evidence they would need before they would accept these extraordinary claims and not dismiss them as ‘spontaneous remission’ or ‘placebo effect’.

Copyright 2009 Jane Thurnell-Read Natural Medicine Shop