Methodological Considerations in the Assessment of Effectiveness of Homeopathic Care: A Critical Review of the EPI3 Study

Abstract

Abstract Background  EPI3 is an observational study of a representative sample of general practitioners (GPs) and patients in France, demonstrating that patient characteristics differ according to the prescribing preferences of their GPs for homeopathy. For selected conditions (musculoskeletal disorders, sleep disorders, anxiety/depression, upper respiratory tract infections), progression of symptoms and adverse events over follow-up in the homeopathy preference group did not significantly differ from other practice preferences, but there was a two-fold to four-fold lower usage of conventional medicines. The EPI3 study's validity was challenged due to absence of head-to-head comparison of medicines to conclude on a causal association between homeopathy and outcomes. Methods A critical review of the nine EPI3 publications was conducted, focusing on generalizability, selection bias, outcome measurements and confounding. Results The conceptual framework of EPI3 rests on a systemic construct, i.e., the homeopathic treatment concept assessed using the type of GP prescribing preference, taking into account the clinical, human and social aspects. The enrollment process enhanced the generalizability of findings. Validated instruments for outcome measurements were used for three conditions, and control of confounding was rigorous. Conclusion EPI3 was conducted according to best practices. Homeopathy prescribing preference met specific patient needs with less use of conventional medicines and without an apparent loss in therapeutic opportunity.