The clinical effects that many alternative practitioners and patients report for homeopathy are placebo and context effects, and further attempts to scientifically justify the 200-year-old system should now be abandoned, according to the authors of a new analysis.
A group of European investigators led by Aijing Shang, Ph.D., of the University of Berne (Switzerland), identified 110 placebo-controlled trials of homeopathy and matched the trials with 110 conventional medicine trials that studied similar disorders and used similar outcome measures. The average sample size was about 65 participants for both the homeopathy studies and the conventional trials.
The studies were parallel group in design and were placebo controlled, with random or quasi-random assignment of subjects.
The authors postulated that the effects of homeopathy could be explained by methodologic deficits and reporting bias, and that the effects of conventional medicine treatments could not be explained by these factors.
Initial analyses suggested that both homeopathy and allopathy showed beneficial effects, but a meta-regression of those trials considered to be of higher methodologic quality suggested that bias played a larger part in the homeopathy trials. The authors wrote, “When analyses were restricted to large trials of higher quality, there was no convincing evidence that homeopathy was superior to placebo, whereas for conventional medicine an important effect remained” (Lancet 2005;366:726–32).
But the authors went on to say that the clinical effects of homeopathy extend beyond the specific effects that the studies were designed to detect. “Context effects,” they noted, can be a significant aspect of therapeutic interventions, with the relationship between the patient and homeopath being a particularly important component. “Practitioners of homeopathy can form powerful alliances with their patients, because patients and caregivers commonly share strong beliefs about the treatment's effects, and other cultural beliefs, which might be both empowering and restorative.”
They recommended that further research focus on these context effects and the potential place of homeopathy in the overall health care system, rather than on additional placebo-controlled trials and metaanalyses.
An unsigned editorial that accompanied the report echoed that sentiment. The Lancet editors wrote, “Surely the time has passed for selective analyses, biased reports, or further investment in research to perpetuate the homeopathy versus allopathy debate. Now doctors need to be bold and honest with their patients about homeopathy's lack of benefit, and with themselves about the failings of modern medicine to address patients' needs for personalized care.”