quack

quack

Monday 9 April 2012

pondering on the placebo effect...


The placebo effect was first mentioned in clinical trials as the baseline effect of healing which may occur just by taking a pill.  It has been found that the very look of the pill, including for example colour may affect how effective it is at supporting healing (Heller et al, 2005, pp.144-148).  The word ‘placebo’ comes from the Latin word meaning ‘it pleases’.   The idea is that just by taking something that looks like medicine, the belief can help someone to get better.  There is a converse to this idea:  the ‘nocibo’ (meaning ‘it harms’) – which might be exemplified by the classic African witch doctor causing someone to believe they will die, and dying, apparently just by the belief (Evans Pritchard, 1937).

The tendency is for orthodox medicine to dismiss the placebo effect as something unimportant.  And Complementary and Alternative Medicines (CAMs) have been dismissed as just placebos.  Some CAM therapists may rejoin by making the point that if a placebo can have some power, would it not be worth exploring this further.  Having said this, most CAM therapists think there is more going on with their treatment than just the belief that it may have an effect.

There was a dramatic study conducted in Texas where conventional doctors gave sham surgery to people with serious knee problems, and concluded that the significant improvements in all participants (operated and sham operated) were all placebo effect (Moseley et al 2002 and BBC2 and Open University 2006).  Interestingly, medical doctors themselves who conduct these operations have often said that they do not know why they work (e.g. Colquhoun, 2006).
 Davidson (2010, personal communication) asserted that shiatsu is more than placebo because the actual touch is inevitably having an effect, which seems plausible to me.  Brown (2012) suggests that shiatsu acts as a catalyst for self-healing, which also seems plausible to me.  I’m not sure how to disentangle these and whether, in a way, it matters.  What do you think?

  
BBC2 and The Open University (2006) ‘Healing’ 31st January, presented by Kathy Sykes.
Brown, T (2012) ‘Chair’s report’ Shiatsu Society Journal, Spring, issue 121.
Colquhoun, D (2006) ‘Improbable Science’ blog, [date accessed 9th April 2012].
Evans Pritchard, E E (1937) ‘Witchcraft, Oracles and Magic among the Azande’, The Clarendon Press, Oxford.
Heller, T, Heller, D, and Yamey, G (2005) ‘A critical look at orthodox medical approaches’ in Lee-Treweek, G, Heller, T, MacQueen, H, Stone, J and Spurr, S, Abingdon, The Open University/Routledge.
Moseley, J. B, O'Malley, K, Petersen, N J., Menke, T J., Brody, B A., Kuykendall, D H, Hollingsworth, J C, Ashton, C M, and Wray, N P. (2002) ‘A Controlled Trial of Arthroscopic Surgery for Osteoarthritis of the Knee’ N Engl J Med, 347, pp. 81-88.