title: Strong heterogeneity of outcome reporting in systematic reviews.
abstract: The Core Outcome Measures in Effectiveness Trial initiative aims at developing core outcome set (COS) for research. Consensus on a COS for renoprotection research is lacking. We performed a systematic review (SR) of SRs of renoprotection to identify outcomes used in renoprotection research and to assess how frequently these outcomes could be meta-analyzed in the SRs.
  
  
  
  We searched for SRs with meta-analyses of renoprotection treatments in the Database of Abstracts of Reviews of Effects and in MEDLINE and collected outcomes that were meta-analyzed. For each outcome and SR, we assessed the proportion of trials/patients that could be meta-analyzed.
  
  
  
  We retrieved 66 SRs. A total of 609 outcomes were extracted for 20 distinct renoprotection outcomes. The median (interquartile range) proportion of SRs in which these outcomes had been meta-analyzed was 8% (2%, 27%) (range 2-50%). The proportion of trials that had been aggregated was >75% for only 36% of the outcomes.
  
  
  
  The outcomes meta-analyzed in renoprotection trials are heterogeneous, with a low proportion of trials or patients pooled for each outcome and each SR. A COS is needed in renoprotection research to limit this waste of research. The outcomes identified in the present work could be a basis for this COS.
authors.affiliation: Centre de Recherche Épidémiologie et Statistique Sorbonne Paris Cité - Inserm UMR 1153, 1 place du Parvis Notre-Dame, 75004 Paris, France; Service de Néphrologie et Immunologie Clinique, CHRU de Tours, 2 Boulevard Tonnellé, 37000 Tours, France; Faculté de Médecine, Université Francois Rabelais, 10 boulevard Tonnellé, 37000 Tours, France. Electronic address: benedicte.sautenet@univ-tours.fr.
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Sautenet
authors.affiliation: Centre de Recherche Épidémiologie et Statistique Sorbonne Paris Cité - Inserm UMR 1153, 1 place du Parvis Notre-Dame, 75004 Paris, France; Faculté de Médecine, Université Francois Rabelais, 10 boulevard Tonnellé, 37000 Tours, France; Service de Réanimation Médicale, CHRU de Tours, 2 Boulevard Tonnellé, 37000 Tours, France.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Contentin
authors.affiliation: Faculté de Médecine, Université Francois Rabelais, 10 boulevard Tonnellé, 37000 Tours, France; Service de Médecine Interne, CHRU de Tours, 2 boulevard Tonnellé, 37000 Tours, France.
authors.forename: Adrien
authors.initials: A
authors.lastname: Bigot
authors.affiliation: Centre de Recherche Épidémiologie et Statistique Sorbonne Paris Cité - Inserm UMR 1153, 1 place du Parvis Notre-Dame, 75004 Paris, France; Faculté de Médecine, Université Francois Rabelais, 10 boulevard Tonnellé, 37000 Tours, France; Centre d'Investigation Clinique, CHRU de Tours, 2 boulevard Tonnellé, 37000 Tours, France; Unité biométrie, Inserm CIC 1415, 2 boulevard Tonnellé, 37000 Tours, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Giraudeau
mesh_terms: D015340:Epidemiologic Research Design; D019317:Evidence-Based Medicine / Q000379:methods; D006801:Humans; D015201:Meta-Analysis as Topic; D017063:Outcome Assessment, Health Care / Q000379:methods*; D012196:Review Literature as Topic
keywords: Chronic kidney disease; Core outcome set; Meta-analysis; Outcome measure; Renoprotective intervention; Systematic review