In February 2004, the U.S. Food and Drug Administration (FDA) prohibited the sale of dietary supplements containing ephedrine alkaloids (ephedra), stating that such supplements present an unreasonable risk of illness or injury. The Dietary Supplement Health and Education Act (DSHEA) of 1994 (21 USC §301, 1994) governs dietary supplement regulation in the U.S. DSHEA places the burden of proof for safety on the government rather than on the manufacturer and thus differs significantly from regulations that govern the marketing of drugs. Part of the evidence the FDA used in reaching its decision was a systematic review of the efficacy and safety of ephedra conducted by the Southern California Evidence-Based Practice Center. In addition to a meta-analysis of controlled trial data, the review contained an evaluation of observational case report data, a study design that has limited inferential abilities regarding cause and effect.
¶
How did the FDA decide what data were relevant to its decision? How did the FDA argument for the ban differ from a decision based solely on statistical hypothesis testing? This paper will address these questions by describing the systematic review approach, the evidence presented, the interpretation of that evidence by those on both sides of the argument and the process by which the decision was made.