title: Predictors of remission with placebo using an integrated study database from patients with major depressive disorder.
abstract: OBJECTIVE
  To identify predictors of remission with placebo treatment in double-blind randomized controlled trials (RCTs) in major depressive disorder (MDD).
  
  
  METHODS
  A total of 1017 placebo-treated patients with baseline Hamilton Depression rating scale (HAMD) total ≥15 from eight duloxetine RCTs were included. Remission was defined as endpoint (7-8 weeks) HAMD total ≤7. Data were randomly split into training data (N = 813, 80%) for model selection and test data (N = 204, 20%) for validation. Logistic regression and classification and regression tree (CART) methods were used to identify predictors of remission. Predictive accuracy of models was assessed by Receiver Operator Characteristic (ROC) curves.
  
  
  RESULTS
  Baseline predictors for remission with placebo consistently identified with the logistic regression and CART analysis were less severe depressive symptoms (based on HAMD core symptoms), younger age, less anxiety (based on HAMD anxiety/somatization), and shorter current MDD episode duration. Associated cut-off values from the CART method characterized patient groups according to their remission likelihood. However, the predictive accuracy was modest for both methods with areas under the ROC curve of 0.6-0.65 based on test data.
  
  
  CONCLUSIONS
  The derived models, although of limited value for predicting remission in individual patients, may be useful for adjusting for placebo effects in clinical trials.
authors.affiliation: Department of Psychiatry, University of California, San Francisco, CA 94143, USA. craign@lppi.ucsf.edu
authors.forename: J C
authors.initials: JC
authors.lastname: Nelson
authors.forename: Q
authors.initials: Q
authors.lastname: Zhang
authors.forename: W
authors.initials: W
authors.lastname: Deberdt
authors.forename: L B
authors.initials: LB
authors.lastname: Marangell
authors.forename: O
authors.initials: O
authors.lastname: Karamustafalioglu
authors.forename: I A
authors.initials: IA
authors.lastname: Lipkovich
mesh_terms: D000328:Adult; D017668:Age of Onset; D000928:Antidepressive Agents / Q000627:therapeutic use; D003865:Major Depressive Disorder / Q000188:drug therapy* / Q000453:epidemiology; D004311:Double-Blind Method; D000068736:Duloxetine Hydrochloride; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D015990:Placebo Effect; D011569:Psychiatric Status Rating Scales; D012372:ROC Curve; D016032:Randomized Controlled Trials as Topic; D012044:Regression Analysis; D012074:Remission Induction; D013876:Thiophenes / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000928:Antidepressive Agents; D013876:Thiophenes; D000068736:Duloxetine Hydrochloride