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Ben Goldacre’s March 1st Bad Science piece for the Guardian, Don’t laugh, sugar pills are the future, in which he comments on the latest research to show that SSRIs are not much more effective than placebo in treating depression is, as usual, a bit thin on the ground with the actual science itself, even if his title might turn out to be remarkably prescient. And, wonder of wonders, I even agree wholeheartedly with a substantial amount of his earlier piece on February 27th, based on the same study, A quick fix would stop drug firms bending the truth. But far more interesting is the piece by Clive Cookson in the FT, Is there an ethical way to fine-tune the placebo effect?

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A lot of hot air has been expended on homeopathy’s apparent inability to “prove” itself in clinical trials. Many people, many of whom call themselves scientists, seem only to need this fact, plus the therapy’s apparent implausibility, to jump to the conclusion the whole thing is nonsense on stilts, and work themselves up into lathers of righteous indignation about the fact that it continues to be practiced. I’ve gone into this a couple of times in the comments to posts on this blog, but this question really does deserve detailed examination, because the issue is not at all as simple as it might seem.

The presupposition of clinical trials is that there is a stable, locally active cause that is only active in the treatment group, irrespective of blinding and the circumstances of the trial or any changed clinical context as a result of the trial. In plain English, this means that the whole basis of clinical trials is predicated on the assumption that the bulk of the treatment effect resides in the physical substance that’s being trialed. It’s a localist hypothesis, proceeding — in homeopathy’s case — from the following logic:

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This is the second paragraph from Ben Goldacre’s recent comment piece Benefits and risks of homeopathy in The Lancet’s November 17 edition.

During the cholera epidemic in the 19th century, death rates at the London Homoeopathic Hospital were three times lower than those at the Middlesex Hospital. (6) The reason for homoeopathy’s success in this epidemic is even more interesting than the placebo effect. At the time, nobody could treat cholera, and while medical treatments such as blood-letting were actively harmful, the homoeopaths’ treatments were at least inert.

(6) Hempel S. The medical detective. London, UK: Granta Books, 2006

Notice how Goldacre doesn’t give us the actual figures. (And this is The Lancet, not the Guardian.) Neither does he clarify that his reasoning is speculation, not established fact. The actual mortality percentages would allow readers to make some kind of sensible judgement about his conjecture that medical treatments exacerbated mortality while homeopathic treatment equated to no treatment at all.

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This is the first paragraph from Ben Goldacre’s recent comment piece Benefits and risks of homeopathy in The Lancet‘s November 17 edition.

Five large meta-analyses of homoeopathy trials have been done. All have had the same result: after excluding methodologically inadequate trials and accounting for publication bias, homoeopathy produced no statistically significant benefit over placebo. 1–5

(1) Kleijnen J, Knipschild P, ter Riet G. Clinical trials of homoeopathy. BMJ 1991; 302: 316–23.
(2) Boissel JP, Cucherat M, Haugh M, Gauthier E. Critical literature review on the effectiveness of homoeopathy: overview of data from homoeopathic medicine trials. Brussels, Belgium: Homoeopathic Medicine Research Group. Report to the European Commission. 1996: 195–210.
(3) Linde K, Melchart D. Randomized controlled trials of individualized homeopathy: a state-of-the-art review. J Alter Complement Med 1998; 4: 371–88.
(4) Cucherat M, Haugh MC, Gooch M, Boissel JP. Evidence of clinical efficacy of homeopathy: a meta-analysis of clinical trials. Eur J Clin Pharmacol 2000; 56: 27–33
(5) Shang A, Huwiler-Müntener K, Nartey L, et al. Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy. Lancet 2005; 366: 726–32

Note that Goldacre omits the Linde et al meta-analysis published in The Lancet in 1997 (6) from his listed studies.

Below are comments and conclusions from each of these studies. Remember, Goldacre is saying that they each support his assertion that homeopathy has no statistically significant benefit over placebo.

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OK. Enough is enough. Everyone’s entitled to their own opinions, but when they start claiming their opinions are ‘scientific’, write comments in learned journals quoting published papers in support of their arguments which don’t actually support their arguments at all, misrepresent statistics and generally twist things so far around their little fingers it defies belief, then if you’re a scientist, a homeopath, both or neither, it’s time to put the record straight.

Dr Ben Goldacre, junior doctor and journalist for the UK Guardian, has been adopting a high profile of late. His attacks on alternative therapies, and homeopathy in particular, have reached such a fever pitch it resembles more of a witch-hunt than a scientific debate. Of course all spindoctors know that if you repeat something often enough, sooner or later people start to believe it, whether it’s true or not. Goldacre’s writings, featuring a persuasive mix of jocular sarcasm, apparent scientific plausibility and fearmongering, would have you believe there’s now scientific consensus from unanimous evidence proving that homeopathy is no more than placebo. It’s one thing to publish that in the popular press, another entirely when it appears in The Lancet.

There is, in fact, no factual basis for these assertions. The evidence Goldacre cites doesn’t back up his claims and the ‘science’ he claims to champion is little more than opinion and spin. Of course I don’t expect you to believe me just because I said so, or even because I include citations (1) of papers published in peer reviewed journals in my footnotes. I’m not even asking you to believe me. I’m asking you to look at the actual scientific proof itself, and to do so with a thorough and critical eye.

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