title: Survey of new 2007 and 2011 Cochrane reviews found 37% of prespecified outcomes not reported.
abstract: OBJECTIVE
  To survey the outcomes used in Cochrane Reviews, as part of our work within the Core Outcome Measures in Effectiveness Trials Initiative.
  
  
  METHODS
  A descriptive survey of Cochrane Reviews, divided by Cochrane Review Group (CRG), published in full for the first time in 2007 and 2011. Outcomes specified in the methods section of each review and outcomes reported in the results section of each review were of interest, in this exploration of the common use of outcomes and core outcome sets (COS).
  
  
  RESULTS
  Seven hundred eighty-eight reviews, specifying 6,127 outcomes, were included. When we excluded specified outcomes from the 86 reviews that did not include any studies, we found that 1,996 (37%) specified outcomes were not reported. Of the 361 new reviews with studies from 2011, 113 (31%) had a "summary of findings" table (SoF). Fifteen broad outcome categories were identified and used to manage the outcome data. We found consistency in the use of these categories across CRGs but inconsistency in outcomes within these categories.
  
  
  CONCLUSIONS
  COS have been used rarely in Cochrane Reviews, but the introduction of SoF makes the development and application of COS timelier than ever.
authors.affiliation: School of Nursing & Midwifery, Trinity College Dublin, 24 D'Olier Street, Dublin 2, Ireland. Electronic address: smithv1@tcd.ie.
authors.forename: Valerie
authors.initials: V
authors.lastname: Smith
authors.affiliation: All-Ireland Hub for Trials Methodology Research, Queens University Belfast, Grosvenor Road, Belfast BT12 6BA, Northern Ireland.
authors.forename: Mike
authors.initials: M
authors.lastname: Clarke
authors.affiliation: MRC North West Hub for Trials Methodology Research, University of Liverpool, Liverpool, L69 3GS, UK.
authors.forename: Paula
authors.initials: P
authors.lastname: Williamson
authors.affiliation: Department of Biostatistics, University of Liverpool, Liverpool, L69 3GA, UK.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Gargon
mesh_terms: D002986:Clinical Trials as Topic; D006306:Health Surveys; D006801:Humans; D017063:Outcome Assessment, Health Care; D011643:Publishing / Q000592:standards*; D012196:Review Literature as Topic; D015983:Selection Bias
keywords: COMET; COS; Cochrane collaboration; Core outcome set; Outcome measurement; Systematic reviews