title: Consistency of atypical antipsychotic superiority to placebo in recent clinical trials.
abstract: BACKGROUND
  The use of control placebos in clinical trials of new antipsychotic medications is increasingly under examination. The active controlled equivalence study could offer a potential alternative design. First, however, it must be clear that any proposed standard control agent has been consistently superior to placebo in previous studies.
  
  
  METHODS
  Through a Freedom of Information Act request, we identified nine placebo-controlled trials of risperidone, olanzapine, or quetiapine.
  
  
  RESULTS
  Meta-analysis indicated that the pooled estimate of the true population effect size +/- SE was 0.46 +/- 0.06 for categorical response rates and >0.53 +/- 0.07 for the continuous Brief Psychiatric Rating Scale change score outcome measure. If the desired detectable effect size is set very conservatively at a 95% confidence lower bound for the estimate of true effect size, statistical power for random samples of 80 per group drawn from a population of subjects similar to that of the nine meta-analyzed studies is.67 for categorical response rates and >.82 for the continuous measure, based on one-sided alpha =.05.
  
  
  CONCLUSIONS
  These data suggest substantial confidence that a therapeutic dose of an atypical antipsychotic will be statistically superior to placebo in an adequately sized randomized trial, when reporting a continuous measure as the principal outcome.
authors.affiliation: Treatment Research Program, Connecticut Mental Health Center, New Haven, CT 06519, USA.
authors.forename: S W
authors.initials: SW
authors.lastname: Woods
authors.forename: M
authors.initials: M
authors.lastname: Stolar
authors.forename: M J
authors.initials: MJ
authors.lastname: Sernyak
authors.forename: D S
authors.initials: DS
authors.lastname: Charney
mesh_terms: D014150:Antipsychotic Agents / Q000627:therapeutic use*; D001569:Benzodiazepines; D002986:Clinical Trials as Topic; D003987:Dibenzothiazepines / Q000627:therapeutic use; D006801:Humans; D000077152:Olanzapine; D010890:Pirenzepine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000188:drug therapy*; D000069348:Quetiapine Fumarate; D018967:Risperidone / Q000627:therapeutic use
chemical_list: D014150:Antipsychotic Agents; D003987:Dibenzothiazepines; D001569:Benzodiazepines; D000069348:Quetiapine Fumarate; D010890:Pirenzepine; D018967:Risperidone; D000077152:Olanzapine