title: Comparison of meta-analytic results of indirect, direct, and combined comparisons of drugs for chronic insomnia in adults: a case study.
abstract: BACKGROUND
  Our Center recently conducted a systematic review of the manifestations and management of chronic insomnia in adults. The efficacy and safety of benzodiazepines and nonbenzodiazepines, relative to placebo, were compared indirectly.
  
  
  OBJECTIVE
  Determine how the results of indirect comparisons made in the review compare with the results of direct comparisons, as well as with estimates derived from Bayesian mixed treatment comparisons. Establish general appropriateness of the use of results of indirect or mixed treatment comparisons.
  
  
  METHODS
  Treatments were compared using frequentist direct, indirect, and combined methods, as well as Bayesian direct and mixed methods.
  
  
  RESULTS
  Estimates for comparisons tended to be clinically and statistically similar across methods. Estimates obtained through indirect comparisons were not biased and were similar to those obtained through direct analysis.
  
  
  CONCLUSIONS
  Results of indirect comparisons made in the review, accurately reflected the current evidence. Frequentist and Bayesian methods of analysis of indirect comparisons should be considered when performing meta-analyses.
authors.affiliation: Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada. bv1@ualberta.ca
authors.forename: Ben W
authors.initials: BW
authors.lastname: Vandermeer
authors.forename: Nina
authors.initials: N
authors.lastname: Buscemi
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Liang
authors.forename: Manisha
authors.initials: M
authors.lastname: Witmans
mesh_terms: D000328:Adult; D001499:Bayes Theorem; D001569:Benzodiazepines / Q000008:administration & dosage / Q000627:therapeutic use; D002908:Chronic Disease; D004359:Drug Therapy, Combination; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D015201:Meta-Analysis as Topic; D015233:Models, Statistical; D009010:Monte Carlo Method; D012196:Review Literature as Topic; D012680:Sensitivity and Specificity; D007319:Sleep Initiation and Maintenance Disorders / Q000188:drug therapy*
chemical_list: D006993:Hypnotics and Sedatives; D001569:Benzodiazepines