Are the clinical effects of homoeopathy placebo effects? – Authors' reply

Abstract

For homoeopathy, there are two mainareas of concern: there is the question of its efficacy and there is the continued debate about its usefulness. Aijing Shang and colleagues1Shang A Huwiler-Müntener K Nartey L et al.Are the effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy.Lancet. 2005; 366: 726-732Summary Full Text Full Text PDF PubMed Scopus (605) Google Scholar revisit the findings of various placebo-controlled trials comparing the efficacies of homoeopathy and allopathy. In the end, Shang and colleagues lend further credence to the notion that the clinical effects of homoeopathy are placebo effects. Their findings seem convincing. However, this does not resolve the problem of treating patients. In my opinion, it does not make any sense to oppose an efficient homoeopathic treatment prescribed for well defined indications. Then, there is also the question of the relative efficacy of homoeopathic versus allopathic treatment for such common and often trivial ailments as bronchitis or common cold. Although not recommended, antibiotics and cortisone are widely prescribed for common cold and bronchitis, especially in France. I launched my medical career in the 1970s, and it was not an uncommon medical practice throughout that decade and the early part of the next to treat pregnancy-induced anaemia with blood transfusions and childhood infections with immunoglobulins. It needs no reiteration that many of those who received such treatments are now carriers of hepatitis C. These patients might have benefited from homoeopathy. It is doubtful that anyone would ever prescribe a compound with widely known placebo effects. Would any physician tell his patient he was prescribing something that, although not effective, might work? A compound is unlikely to act as a placebo when the recipient knows that its only effects are as such. I have been pursuing scientific activities for nearly three decades. I do not believe that there is anything active in homoeopathic pills. However, I feel that we have not yet assessed the potential usefulness of homoeopathic medication in the context of inappropriately prescribed allopathic medications or receipt of no medication at all. In such settings, the cost-effectiveness of homoeopathic therapy should be compared with that of allopathic medication. The age-old dictum Primum non nocere still holds true. From this viewpoint, homoeopathy should be assessed as a possible competitor to allopathy. I declare that I have no conflict of interest. Are the clinical effects of homoeopathy placebo effects?Aijing Shang and colleagues (Aug 27, p 726)1 show that small-study bias pervades all clinical research. They suggest that, for homoeopathy, this observation is a mortal blow because the combined odds ratios of the largest homoeopathy trials converge to zero. We believe that there are some flaws in this argument. Full-Text PDF Are the clinical effects of homoeopathy placebo effects?We congratulate Aijing Shang and colleagues1 on their meta-analysis examining the clinical effects of homoeopathy. Their methods largely reproduce those of our meta-analysis on the same topic published in The Lancet 8 years ago.2 We agree that homoeopathy is highly implausible and that the evidence from placebo-controlled trials is not robust. However, there are major problems with the way Shang and colleagues present and discuss their results, as well as how The Lancet reviewed and interpreted this study. Full-Text PDF Are the clinical effects of homoeopathy placebo effects?We wish to raise concerns about the meta-analysis of homoeopathy by Aijing Shang and colleagues.1 It is based on 110 trials of homoeopathy and 110 of conventional medicine, which are said to be matched, although the criteria are not clearly stated. They were not well matched for at least one crucial parameter—trial quality—which was higher for the homoeopathy studies. Full-Text PDF Are the clinical effects of homoeopathy placebo effects?The scientific debate on the effects of homoeopathy is not over, despite your Editorial1 and Jan Vandenbroucke's Comment2 on the paper by Aijing Shang and colleagues,3 in which 110 trials of homoeopathy were compared with 110 trials of allopathy. Shang and colleagues unsurprisingly showed that both interventions had a beneficial effect, but their finding that higher-quality papers were 2·6 times more prevalent in homoeopathic trials than allopathic trials is unexpected. Between-trial heterogeneity was also more pronounced in the allopathic sample. Full-Text PDF