title: Clinical trials and systematic reviews addressing similar interventions for the same condition do not consider similar outcomes to be important: a case study in HIV/AIDS.
abstract: BACKGROUND
  The usefulness of clinical trials and systematic reviews is compromised when they report different outcomes. We compared outcomes in reviews of HIV/AIDS and the trials included in the reviews.
  
  
  METHODS
  We examined all Cochrane reviews of HIV/AIDS (as of June 2013) that included ≥1 trial and the trials that the reviews included. We compared outcomes within subgroups defined by type of intervention: clinical management, biomedical prevention, behavioral prevention, and health services.
  
  
  RESULTS
  We included 84 reviews that encompassed 524 trials. Although the median number of outcomes per trial (8) and per review (7.5) was similar, the trials reported a considerably greater number of unique outcomes than the reviews (779 vs. 218), ranging from 2.3 times greater (clinical management) to 5.4 times greater (behavioral prevention). High proportions of trial outcomes were not in any review: 68% (clinical management) to 83% (behavioral prevention). Lower proportions of review outcomes were not in any trial: 11% (clinical management) to 39% (health services).
  
  
  CONCLUSIONS
  Outcomes in trials and reviews are not well aligned for appropriate inclusion of trial results in reviews and meta-analyses. Differences in perspectives, goals, and constraints between trialists and reviewers may explain differences in outcomes they consider important.
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Room W6507-B, Baltimore, MD 21205, USA. Electronic address: isaldan1@jhmi.edu.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Saldanha
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Room E6011, Baltimore, MD 21205, USA.
authors.forename: Tianjing
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Health, Behavior, and Society, Johns Hopkins Bloomberg School of Public Health, 2213 McElderry Street, 2nd floor, Baltimore, MD 21205, USA.
authors.forename: Cui
authors.initials: C
authors.lastname: Yang
authors.affiliation: Department of Health, Behavior, and Society, Johns Hopkins Bloomberg School of Public Health, 624 North Broadway, Room 739, Baltimore, MD 21205, USA.
authors.forename: Jill
authors.initials: J
authors.lastname: Owczarzak
authors.affiliation: MRC North West Hub for Trials Methodology Research, Department of Biostatistics, University of Liverpool, Shelley's Cottage, Brownlow Street, Liverpool L69 3GS, UK.
authors.forename: Paula R
authors.initials: PR
authors.lastname: Williamson
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Room E6152, Baltimore, MD 21205, USA.
authors.forename: Kay
authors.initials: K
authors.lastname: Dickersin
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods* / Q000706:statistics & numerical data*; D015658:HIV Infections / Q000628:therapy*; D006801:Humans; D017063:Outcome Assessment, Health Care / Q000379:methods / Q000706:statistics & numerical data*; D012196:Review Literature as Topic
keywords: Clinical trials; Core outcome sets; HIV/AIDS; Outcome selection; Outcomes; Systematic reviews