Placebo Response in Studies of Major Depression

CONTEXT: Intense debate persists about the need for placebo-controlled groups in clinical trials of medications for major depressive disorder (MDD). There is continuing interest in the development of new medications, but because effective antidepressants are already available, ethical concerns have been raised about the need for placebo groups in new trials. OBJECTIVE: To determine whether the characteristics of placebo control groups in antidepressant trials have changed over time. DATA SOURCES AND STUDY SELECTION: We searched MEDLINE and PsychLit for all controlled trials published in English between January 1981 and December 2000 in which adult outpatients with MDD were randomly assigned to receive…