Letters: Observing the benefits of placebos
Wednesday August 31, 2005
Ben Goldacre’s thought-provoking piece (A tonic for sceptics, August 29) moves forward the debate about homeopathy and complementary and alternative medicine (CAM). The argument is no longer about whether homeopathy works, but how it works. He is absolutely right, therefore, to single out the placebo effect as “the most interesting phenomenon in medicine”, and that it goes into the cultural meaning of treatment. But it’s a pity he stopped there, for the whole of western science is also culturally defined. For homeopathy, this raises two issues – one theoretical, the other practical.
First, the observation problem. Physics teaches us that reality and our observation of it cannot be separated. The corollary – that any attempt at such separation can essentially destroy the “reality” under observation – is precisely what is perpetrated during blinded trials of homeopathy. Consequently, the double blind placebo-controlled trial, as applied to homeopathy and CAM, is the scientific equivalent of Nelson putting a telescope to his blind eye.
Second, if Goldacre believes “that in many cases, homeopathy does seem to help, as a complex intervention” albeit one that is “placebo, in all its rich glory” then there is no further need for debate. However homeopathy is deemed to “work”, it should be available alongside conventional medicine, where apart from its therapeutic benefits, its non-toxic and economic advantages would be appreciated.
Why is it that only the negative research results about homeopathy get the headlines? Take, for instance, the research done at the Institute for Pharmacy at the University of Leipzig: using concentrations of belladonna which were literally less than a drop in the ocean, statistically significant changes in the contractions of the gut of rats were measured consistently and repeatedly. The study used double-blind techniques designed to detect the placebo effect. It compared results obtained by following precisely the special stirring techniques used in homeopathy, or by ignoring them, and found a positive correlation in favour homeopathy.