title: Clinic visits in late-life depression trials: effects on signal detection and therapeutic outcome.
abstract: OBJECTIVE
  This meta-analysis investigated how the supportive care provided in antidepressant clinical trials for late-life depression influences response and drop-out rates.
  
  
  METHODS
  Medline, PsycINFO, and PubMed were searched to identify trials contrasting antidepressants with placebo or active comparator in outpatients aged at least 60 years with major depressive disorder. Hierarchical linear modeling was used to determine whether treatment assignment (medication versus placebo), study type (placebo-controlled or comparator), study duration, and the number of study visits affected response and attrition rates.
  
  
  RESULTS
  In the response rate analysis, a significant interaction was found between study visits and treatment assignment (odds ratio [OR]: 0.89, t = -2.186, df = 36, p = 0.035), such that each additional visit over the grand mean for the sample increased average placebo response by 2.5% while not significantly affecting medication response. Controlling for other variables, the effect of this interaction was to dramatically decrease average medication versus placebo differences in trials having greater numbers of study visits. Neither the number of study visits (OR: 0.96, t = -0.468, df = 14, p = 0.646) nor the treatment × visits interaction (OR: 1.03, t = 0.463, df = 35, p = 0.645) influenced drop-out rates.
  
  
  CONCLUSIONS
  Increased supportive care in the form of clinic visits leads to greater placebo but not antidepressant medication response in clinical trials for late-life depression. Less frequent visit schedules may increase average medication-placebo differences in randomized controlled trials without appreciably increasing drop-out rates.
authors.affiliation: New York State Psychiatric Institute, New York, NY; Columbia University College of Physicians and Surgeons, New York, NY. Electronic address: brr8@columbia.edu.
authors.forename: Bret R
authors.initials: BR
authors.lastname: Rutherford
authors.affiliation: New York State Psychiatric Institute, New York, NY.
authors.forename: Jane
authors.initials: J
authors.lastname: Tandler
authors.affiliation: New York State Psychiatric Institute, New York, NY.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Brown
authors.affiliation: Queens College of the City University of New York, New York, NY.
authors.forename: Joel R
authors.initials: JR
authors.lastname: Sneed
authors.affiliation: New York State Psychiatric Institute, New York, NY; Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: Steven P
authors.initials: SP
authors.lastname: Roose
mesh_terms: D000368:Aged; D000928:Antidepressive Agents / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000188:drug therapy*; D006801:Humans; D009819:Office Visits / Q000706:statistics & numerical data*; D017063:Outcome Assessment, Health Care / Q000592:standards*; D016032:Randomized Controlled Trials as Topic / Q000592:standards*; D012107:Research Design / Q000592:standards*
chemical_list: D000928:Antidepressive Agents
keywords: Antidepressant; major depressive disorder; placebo; randomized controlled trial; signal detection