title: Placebo control groups in trials of major depressive disorder among older patients.
abstract: BACKGROUND
  Ethical concerns have been raised regarding the continued use of placebo control groups in randomized controlled trials of antidepressant medications for major depressive disorder. These concerns may be especially relevant for geriatric patients who may experience significant morbidity related to major depressive disorder.
  
  
  METHODS
  Sixty-eight randomized placebo-controlled trials of antidepressant medication for major depressive disorder were examined, 6 of which measured response to medication and placebo in elderly patients.
  
  
  RESULTS
  Although this review is limited by the small number of studies focusing on older individuals, there are a number of similarities and some differences in geriatric studies in comparison to other studies of adults with major depressive disorder. In comparison to studies of younger adults, the proportion of patients responding to placebo in studies of older individuals was slightly higher, and the proportion of patients responding to active medication was lower, leading to a significantly reduced effect size.
  
  
  CONCLUSIONS
  The scientific importance of using control groups in studies of major depression poses ethical challenges. However, the substantial and variable response to placebo and the inability to predict accurately the response to placebo or medication raise serious doubts about the scientific value of trials of new medications in which there is no placebo group.
authors: College of Physicians and Surgeons, Columbia University, New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA. btw1@columbia.edu
authors: B Timothy
authors: BT
authors: Walsh
authors: Robyn
authors: R
authors: Sysko
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000928:Antidepressive Agents / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015990:Placebo Effect; D016032:Randomized Controlled Trials as Topic
chemical_list: D000928:Antidepressive Agents