Newswise — The evidence for a specific effect of homoeopathic remedies is weak, according to an article in this week's issue of The Lancet. The authors conclude that the clinical effects of homoeopathy are compatible with placebo effects.

Matthias Egger (University of Berne, Switzerland) and colleagues compared 110 placebocontrolled, randomised trials of homoeopathy with 110 conventional-medicine trials matched for disorder and type of outcome. The clinical topics studied in the trials ranged from respiratory infections to surgery to anaesthesiology. The researchers looked at the treatment effects in smaller, low quality trials and larger trials of higher quality. They found, in both groups, that smaller trials of lower quality showed more beneficial treatment effects than larger and higher-quality trials. However, when the analysis was restricted to large trials of high quality there was no convincing evidence that homoeopathy was superior to placebo, whereas for conventional medicine an important effect remained.

Professor Egger concludes: "Our study powerfully illustrates the interplay and cumulative effect of different sources of bias. We acknowledge that to prove a negative is impossible, but we have shown that the effects seen in placebo-controlled trials of homeopathy are compatible with the placebo-hypothesis."

In an accompanying Comment Jan Vandenbroucke (Leiden University Medical Centre, Netherlands) states: "Science is an intrinsically human affair. When new theories are created and new evidence sought, judgement will retain a subjective element. This does not mean that it is impossible to sift out which interpretation is more valuable . . . The ultimate proof is that science make progress in changing reality: in allopathic [conventional] medicine by preventing, alleviating, and curing disease ever more effectively."

In an accompanying Editorial TheLancetcomments: "It is the attitudes of patients and providers that engender alternative-therapy seeking behaviours which create a greater threat to conventional care—and patients' welfare—than do spurious arguments of putative benefits from absurd dilutions . . . Now doctors need to be bold and honest with their patients about homoeopathy's lack of benefit, and with themselves about the failings of modern medicine to address patients' needs for personalised care."

Please remember to cite The Lancet.