Cancer Institute A national cancer institute
designated cancer center

Philip W. Lavori

Publication Details

  • Placebo control groups in randomized treatment trials: A statistician's perspective Lavori, P. W. ELSEVIER SCIENCE INC. 2000: 717-723


    Because a statistical tie between standard treatment and an innovation is uninterpretable, most trials intended to demonstrate efficacy of innovations in psychopharmacology employ a placebo control group, despite the existence of standard medications for many disorders. In this review I consider the statistical issues that inform the ethics of the decision to use a placebo condition and make the following points: 1) the investigator is relying on the assumption that the effects of delayed standard treatment are neither long-lasting nor harmful; 2) the usual practice of truncating follow-up when a patient ceases to adhere to a study treatment makes it difficult to empirically test that assumption; 3) placebo control trials often suffer from methodological weaknesses (including nonrandom truncation) that reduce their inferential power; 4) these subtleties place a substantial burden on the informed consent process; 5) alternative designs are available but not well explored, due to the dominant role of "regulatory" trial methodology; and 6) researchers should consider other goals besides helping to introduce another treatment that improves on placebos but not the standard treatment.

    View details for Web of Science ID 000086414200007

    View details for PubMedID 10773178

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