In 1991 Kleijnen et al published the first meta-analysis of homeopathy showing that results could compete with conventional medicine. But the opposition became stronger despite this result, even by people who demanded scientific proof before. The same people who demand proof for homeopathy are convinced that homeopathy cannot work. This conviction is based on two misconceptions:
1. Homeopathic doctors expect the same results from a homeopathic potency of a medicinal substance as from a pharmaceutical dose. Vandenbroucke states: “Microbiologists know for sure that infinite dilutions of an antibiotic will never show any effect on bacterial growth”.
2. Medicines can only work as conventional medicines via chemical interactions. Vandenbroucke: “Accepting that infinite dilutions work would subvert more than conventional medicine; it wrecks a whole edifice of chemistry and physics”.
It is amazing how these convictions have become dogmas. No homeopathic doctor will expect any effect on bacterial growth from an infinitely diluted antibiotic. Does the world only consist of chemical interactions? Based on these convictions positive results of homeopathic research can only prove fraud by homeopathic doctors. The only good homeopathic RCT is a negative homeopathic RCT, it will be qualified as good more easily because quality judgements of RCT are quite subjective. And beware, any negative result can and will be used against us!
Some meta-analyses concluded that selections of the available trials proved no efficacy for homeopathy, but this problem also goes for conventional medicine. August 2005 the editor of the Lancet concluded that a meta-analysis by Shang et al meant 'the end of homeopathy'. The publication of this meta-analysis, however, was an outrage to scientific integrity, because essential information was missing, and that was not without reason!
Four months later the missing information was published. Re-analysis of the most important data showed:
- The former conclusion in the Lancet (August 2005) that homeopathy is a placebo-effect appears to be based on biased selection of 8 out of the 110 studies. The analysis of these 8 trials was also flawed.
- Essential information was missing in Shang's paper, like which trials were selected. This information was disclosed 4 months after the publication and re-analysed by Luedtke and Rutten.
- Even in their response to critics 4 months after the publication Shang et al maintained that their conclusion was based on a careful comparison of homeopathy and conventional trials. That was a vicious lie! The 8 conclisive trials were not matched with conventional studies. Several questionnable post-hoc selections were necessary to produce less effect for homeopathy than for conventional medicine.
- The efficacy of homeopathy in 110 scientific studies is the same as the efficacy of 110 comparable conventional studies. If 21 good quality studies are selected the result is still significantly positive.
- Quality of homeopathy studies was better than of conventional studies; for homeopathy 21 studies had good quality, for conventional medicine 9.
- In homeopathy and conventional medicine the same number of trials had no effect.
- Homeopathy is not effective in healthy people (marathon runners), but very effective in the most frequently occurring acute disease: acute upper respiratory tract infections.
- Homeopathy is not only effective, but also safe.
For a comprehensive explanation about the misleading aspects of the Lancet 2005 paper click here.
Former meta-analyses, Kleijnen (1991), Linde (1997) and Cucherat (2000) already showed that proof for homeopathy was comparable to conventional medicine. Linde's analysis showed that the positive result could not be explained by publication bias. Shang's analysis adds that it cannot be explained by quality bias or a combination of publication bias and quality bias. The efficacy of homeopathy is comparable to conventional medicine, even with less publication bias and less quality bias.
The last argument that still seems to stand is referring to Bayes' theory that new information, like meta-analysis, only updates former beliefs to a limited extend. That is true, but the most essential point of bayesian reasoning is taking all evidence into account, also the numerous experiences of patients and all other evidence. For more information, click here .