title: Are all first-generation antipsychotics equally effective in treating schizophrenia? A meta-analysis of randomised, haloperidol-controlled trials.
abstract: OBJECTIVE
  Narrative, unsystematic reviews revealed no differences in efficacy between the various first-generation antipsychotics (FGAs) resulting in the psychopharmacological assumption of comparable efficacy between the different FGAs. We sought to determine if the assumption of comparable efficacy of all FGAs can be regarded as evidence-based using meta-analytic statistics.
  
  
  METHODS
  A systematic literature survey (Cochrane Schizophrenia Group trial register) was applied to identify all RCTs that compared oral haloperidol with another oral FGA in schizophrenia. Primary outcome was dichotomous treatment response. Secondary outcomes were symptom severity measured by rating scales, discontinuation rates, and specific adverse effects.
  
  
  RESULTS
  Altogether, 79 RCTs with 4343 participants published between 1962 and 1999 were included. We found a significant between-group difference only between haloperidol and nemonapride, but not for the remaining 19 investigated FGAs. There were no significant differences for discontinuation rates.
  
  
  CONCLUSIONS
  As most of the single meta-analytic comparisons can be regarded as underpowered, the evidence for the assumption of comparable efficacy of all FGAs is inconclusive. We therefore cannot confirm or reject the statements of previous narrative, unsystematic reviews in this regard. Our findings were limited by the small sample size in the individual comparisons and the low methodological quality in many included studies.
authors.affiliation: a Department of Psychiatry and Psychotherapy , Medical University of Vienna , Vienna , Austria.|b Department of Psychiatry and Psychotherapy , Technische Universität München , München , Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Dold
authors.affiliation: b Department of Psychiatry and Psychotherapy , Technische Universität München , München , Germany.
authors.forename: Magdolna
authors.initials: M
authors.lastname: Tardy
authors.affiliation: b Department of Psychiatry and Psychotherapy , Technische Universität München , München , Germany.
authors.forename: Myrto T
authors.initials: MT
authors.lastname: Samara
authors.affiliation: c Shanghai Key Laboratory of Psychotic Disorders , Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine , Shanghai , China.
authors.forename: Chunbo
authors.initials: C
authors.lastname: Li
authors.affiliation: a Department of Psychiatry and Psychotherapy , Medical University of Vienna , Vienna , Austria.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Kasper
authors.affiliation: b Department of Psychiatry and Psychotherapy , Technische Universität München , München , Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Leucht
mesh_terms: D014150:Antipsychotic Agents / Q000009:adverse effects / Q000145:classification* / Q000627:therapeutic use*; D001549:Benzamides / Q000009:adverse effects / Q000627:therapeutic use*; D006220:Haloperidol / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D017594:Publication Bias; D016032:Randomized Controlled Trials as Topic; D018401:Sample Size; D012559:Schizophrenia / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D001549:Benzamides; D006220:Haloperidol; C030265:nemonapride
keywords: Schizophrenia; antipsychotics; effect sizes; haloperidol; meta-analysis