title: The impact of restrictive entry criterion during the placebo lead-in period.
abstract: In the study of depression, most randomized clinical trials have design features that attempt to sample from a stable patient population. One commonly used design feature is to require patients to maintain some minimum baseline symptom severity score during a placebo lead-in period. One intent of this design feature is to evaluate the behavior of patients prior to administration of active medication. If, during the lead-in period, patients do not maintain minimum symptom severity, the patients are excluded from the remainder of the study, the theory being that the excluded patients are not part of a stable patient population and hence are not likely to demonstrate efficacy of a truly effective treatment. This presentation investigates the effectiveness of a restrictive entry criterion and proposes an alternative explanation for what is usually defined as placebo response.
authors.affiliation: Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, Indiana 46285, USA. richard.landin@wl.com
authors.forename: R
authors.initials: R
authors.lastname: Landin
authors.forename: D J
authors.initials: DJ
authors.lastname: DeBrota
authors.forename: T A
authors.initials: TA
authors.lastname: DeVries
authors.forename: W Z
authors.initials: WZ
authors.lastname: Potter
authors.forename: M A
authors.initials: MA
authors.lastname: Demitrack
mesh_terms: D000928:Antidepressive Agents / Q000627:therapeutic use; D001699:Biometry; D002986:Clinical Trials as Topic / Q000379:methods* / Q000706:statistics & numerical data; D003863:Depression / Q000188:drug therapy / Q000523:psychology; D006801:Humans; D016014:Linear Models; D010919:Placebos; D016032:Randomized Controlled Trials as Topic / Q000379:methods / Q000706:statistics & numerical data; D016037:Single-Blind Method
chemical_list: D000928:Antidepressive Agents; D010919:Placebos