[Skip to Navigation]
March 7, 2001

Scientific and Ethical Issues in Equivalence Trials

Author Affiliations

Author Affiliations: Interdisciplinary Oncology Program, Division of Blood and Bone Marrow Transplantation, H. Lee Moffitt Cancer Center and Research Institute, University of South Florida, Tampa (Dr Djulbegovic); and Cochrane Centre, NHS Research and Development Program, Summertown Pavilion, Oxford, England (Dr Clarke).

JAMA. 2001;285(9):1206-1208. doi:10.1001/jama.285.9.1206

Any testing of medical treatments is an exercise in comparison. In a typical clinical trial, 2 treatments are compared to determine which is better or if both are the same. Trials designed to address whether one treatment is better than the other may be called superiority trials, whereas those designed to show that 2 treatments are the same are called equivalence trials. However, the design of both types of trials should depend on the uncertainty principle—a fundamental ethical and scientific principle for conducting randomized controlled trials.1