The CIOMS view on the use of placebo in clinical trials.

Based on worldwide consultations with experts in science and ethics the revised CIOMS 2002 International Ethical Guidelines for Biomedical Research Involving Human Subjects provide guidance on when the use of placebo as a comparator in clinical research is ethically acceptable. The article reviews the main points of the CIOMS Guidelines and commentaries including the use of placebo in situations where the best current method is available and the relation of placebo to established effective intervention. It discusses the use of placebo in externally sponsored research in low-resource countries and requirements for informed consent related to placebo studies.