Homeopathy and placebo
29 December 2017 (online)
After reading the article on homeopathic meta-analysis[ 1 ] we would like to make some remarks. The selected ‘large’ studies (eight for homeopathy and six for allopathy) are in fact a small number, indeed, to make clear-cut conclusions, especially if based on meta-analysis of non-homogeneous trials. On such ‘quantitative’ selection, the authors ignored that the ‘size’ of a research does not necessarily meet the ‘qualitative’ internal requirement of a therapeutic technique while, often, depends on the economic power of the promoter/commissioner. The overall reliability of confidence intervals for both areas is decreased by the small number of studies considered. It does not seem correct to use only ‘effect measurement’ criteria, for such different therapeutic techniques, without considering their ‘effectiveness’ which includes side and adverse effects, subjective perception of the therapy and its acceptance, overhead costs and benefits. None of the latter evaluations have been included.
In homeopathy, the ‘improvement’ parameters follow specific rules. These rules do imply the consideration of the totality of a patient's symptoms which includes the disease's symptoms. This totality has not been considered when comparing homeopathy and allopathy, the ‘quality’ criteria applied to homeopathic trials was strictly based on the criteria applied to allopathic randomized trials with placebo. About this key-aspect the paper is quite vague, not specifying how quality rating has been actually applied, and existing literature discussing the problems raised by placebo-controlled trials in homeopathy has been ignored.[ 2 ] The placebo ‘action’ is definitely not due to the activity of the ‘inactive’ substance but to the intrinsic healing capacities and response of the treated subject. This response is also the one that is expected to be triggered by the homeopathic remedy. To successfully discriminate between the placebo and remedy response it is important to know the characteristics of the substance given to the patient and the healing steps of the two different clinical methods. Assuming that the extremely-low dose remedy and the endogenous healing mechanisms interact in a complex way,[ 3 ] the final effect is due to the product of these two factors and any procedure decreasing the latter may markedly affect the homeopathic cure, much more than the allopathic drug effect.
A prejudice against homeopathy is shown by the authors who in the introduction use the word ‘implausible’ and maintain that any effects of homoeopathy ‘must’ be non-specific placebo effects. As a matter of fact, there is much data to support the evidence of a physical and chemical plausibility of homeopathy along with a strong scientific consistency of the principle of similarity,[ 4 ] but this evidence has been ignored.
The authors, as everyone, have the right of publishing their analysis and considerations. Less properly some people used this article to determine ‘the end of homeopathy’. It is quite surprising how fast this article's conclusions, not so strongly supported by data, have reached the media all over the world as if a campaign had been orchestrated. Is meta-analysis an unequivocal tool? According to existing literature it does not appear to be.[ 5 ]
- 1 Shang A., Huwiler-Müntener K., Nartey L., Jüni P., Dörig S., Sterne J.A.C., Pewsner D., Egger M. Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy. Lancet 2005; 366: 726-732.
- 2 Weatherley-Jones E., Thompson E.A., Thomas K.J. The placebo-controlled trial as a test of complementary and alternative medicine: observations from research experience of individualised homeopathic treatment. Homeopathy 2004; 93: 186-189.
- 3 Bellavite P. Complexity science and homeopathy: a synthetic overview. Homeopathy 2003; 92: 203-212.
- 4 Eskinazi D. Homeopathy re-revisited: is homeopathy compatible with biomedical observations?. Arch Intern Med 1999; 159: 1981-1987.
- 5 Linde K., Clausius N., Ramirez G., Melchart D., Eitel F., Hedges L.V., Jonas W.B. Are the clinical effects of homeopathy placebo effects? A meta-analysis of placebo-controlled trials. Lancet 1997; 350: 834-843.