Randomized controlled trials of individualized homeopathy: A state-of-the-art review

Background and objective: Individualized homeopathy is the most controversi al form of this therapy. This review aims to summarize the actual state of clinical efficacy research on individualized homeopathy. Methods: Electronic databases as well as other sources were searched for po ssibly relevant studies. Randomized or quasirandomized controlled clinical trials comparing an individualized homeopathic treatment strategy with plac ebo, no treatment, or another treatment were eligible. Information on patie nts, methods, interventions, outcomes, and results was extracted in a stand ardized manner and quality was assessed using a checklist and two scoring s ystems. Trials providing sufficient data were pooled in a quantitative meta -analysis. Results: A total of 32 trials (28 placebo-controlled, 2 comparing homeopath y and another treatment, 2 comparing both) involving a total of 1778 patien ts met the inclusion criteria. The methodological quality of the trials was highly variable. In the 19 placebo-controlled trials providing sufficient data for meta-analysis, individualized homeopathy was significantly more ef fective than placebo (pooled rate ratio 1.62, 95% confidence interval 1.17 to 2.23), but when the analysis was restricted to the methodologically best trials no significant effect was seen. Conclusion: The results of the available randomized trials suggest that ind ividualized homeopathy has an effect over placebo. The evidence, however, i s not convincing because of methodological shortcomings and inconsistencies . Future research should focus on replication of existing promising studies . New randomized studies should be preceded by pilot studies.