According to one study, much of the scientific research on homeopathy is marred by statistical bias, suggesting that the benefits of these capsules may be overestimated.
Homeopathy comes from the Greek words homoion pathos meaning ‘similar suffering’. In Western countries, more than 9% of adults have used homeopathy in the past 12 months.
The principle behind homeopathy is that “like cures like.” It consists of administering very small doses of substances that induce the same symptoms as the disease. For years, this alternative medicine has divided scientists and governments. A group of researchers analyzed several studies on the subject. In the British Medical Journal, they claim that the effects of homeopathy are overestimated because of biased research methods.
The authors of the study were interested in reporting bias, i.e. the fact that the diffusion of scientific research is influenced by the results. In summary, the clinical studies published on this subject are only a sample of all the scientific studies conducted on homeopathy, and only those whose results prove the effectiveness of these products. To carry out this work, the scientists used the public registries of clinical trials: these were created in 2008 to reduce the risk of reporting bias. “Recording and publishing the results of clinical trials is considered an ethical, though not a mandatory obligation for researchers,” the authors say.
A lack of scientific and ethical standards claim the researchers
Therefore, they wanted to know how many registered trials evaluating homeopathy are not published, whether the main results of the registered trials match the actual published results, and what the total number of registered and published homeopathic trials is. This group of researchers found that since 2002, almost 38% of registered homeopathy trials have not been published, while more than half, 53%, of published randomized controlled trials have not been registered. They also found that homeopathy trials were more likely to be registered after they started and not before. In addition, a quarter of the published results did not match the originally recorded results. “These poor research practices suggest that the actual impact of homeopathy may have been significantly overestimated,” the scientists say. They say these results demonstrate a “troubling lack of scientific and ethical standards in the field of homeopathy and a high risk of bias in reporting.” They want to draw the attention of health professionals to the fact that the published studies on homeopathy represent only a small sample of the total research that has been conducted, and that they mainly highlight positive results about this type of treatment.
NB: The study does not mention whether this type of bias also exists in regular medical clinical studies.