REPLY A Critical Overview of Homeopathy Wayne Jonas, MD IN RESPONSE: Dr. Dantas and colleagues point out that there are additional data beside those presented in our overview of homeopathy. Our purposely limited review omitted some less rigorous science. Determining the magnitude of adverse effects is even more difficult than determining efficacy since most studies are not designed to detect adverse effects. The rate of the latter is extremely low in homeopathy. A more fruitful approach than meta-analysis of efficacy studies is to investigate the potential toxic effects of homeopathic drugs in cell and animal studies (1). Likewise, homeopathic pathogenic trials or "provings," while extensively reported in the literature, are generally not designed to detect effects over placebo. The few high-quality proving studies designed to test differences between homeopathic remedies and placebo do not show such differences because symptoms in the placebo groups apparently covary in parallel with those in the remedy groups (2). Disentangling these remedy–placebo effects may require sequential rather than parallel study designs. Such studies have not been done. The question of sample size is an important one for all clinical research. Sample size (not quality, as stated by Dr. Almeida) is the primary problem with the studies on the homeopathic treatment of diarrhea. Three studies (not 2), all rated as high quality by several independent reviewers, have demonstrated consistent effect sizes on the same outcome measure on the same day. As sample sizes increased, statistical significance improved and confidence intervals narrowed (3). Dr. Almeida’s other comments are illogical and erroneous: 1) The symptoms of Pulsatilla and the criteria for study quality are completely unrelated; 2) the critique by Sampson has been thoroughly debunked (4, 5); 3) Dr. Almeida’s failure to assess treatment model validity leads to erroneous research evaluation and conclusions, which is a common problem in complementary and alternative medicine (6); and 4) his statement that 1 author had $50 million for alternative medicine research is incorrect. We appreciate Dr. Federspil and colleagues’ pointing out that some people practicing a medical system hold metaphysical beliefs about its action. This does not, of course, preclude science from examining the practice in the laboratory or in clinical trials to see whether it works. Walking the razor edge of Occam (that is, being true to the data) is by far the most difficult task faced by investigators when confronted with controversial areas such as homeopathy. Good scientists, however, are willing to get their feet cut by the truth. Annals of Internal Medicine 21 October 2003 | Volume 139 Issue 8 | Page W-76 Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.