title: External validation of severity scoring systems for acute renal failure using a multinational database.
abstract: OBJECTIVE
  Several different severity scoring systems specific to acute renal failure have been proposed. However, most validation studies of these scoring systems were conducted in a single center or in a small number of centers, often the same ones used for their development. Therefore, it is not known whether such severity scoring systems may be widely applied.
  
  
  METHODS
  Prospective clinical investigation.
  
  
  METHODS
  Intensive care units.
  
  
  METHODS
  One thousand seven hundred and forty-two intensive care unit patients with acute renal failure who were either treated with renal replacement therapy or fulfilled predefined criteria.
  
  
  METHODS
  Demographic and clinical information and outcomes were measured.
  
  
  RESULTS
  Scores for four acute renal failure-specific scoring systems and two general scoring systems (Simplified Acute Physiology Score II and Sequential Organ Failure Assessment) were calculated, and their discrimination and calibration were tested with receiver operating characteristic curves and Hosmer-Lemeshow goodness-of fit-tests. For the receiver operating characteristic curves, blood lactate levels were also used as a reference. All scores had an area under the receiver operating characteristic curve <0.7 (Mehta 0.670, Liano 0.698, Chertow 0.610, Paganini 0.643, Simplified Acute Physiology Score II 0.645, Sequential Organ Failure Assessment 0.675, lactate 0.639). For scores that can calculate predicted mortality, the Hosmer-Lemeshow goodness-of-fit test showed poor calibration.
  
  
  CONCLUSIONS
  None of the scoring systems tested had a high level of discrimination or calibration to predict mortality for patients with acute renal failure when tested in a broad cohort of patients from multiple countries. A large, multiple-center database might be needed to improve the discrimination and calibration of acute renal failure scoring system.
authors.affiliation: Department of Intensive Care, Austin Hospital, Melbourne, Australia.
authors.forename: Shigehiko
authors.initials: S
authors.lastname: Uchino
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Morimatsu
authors.forename: Stanislao
authors.initials: S
authors.lastname: Morgera
authors.forename: Miet
authors.initials: M
authors.lastname: Schetz
authors.forename: Ian
authors.initials: I
authors.lastname: Tan
authors.forename: Catherine
authors.initials: C
authors.lastname: Bouman
authors.forename: Ettiene
authors.initials: E
authors.lastname: Macedo
authors.forename: Noel
authors.initials: N
authors.lastname: Gibney
authors.forename: Ashita
authors.initials: A
authors.lastname: Tolwani
authors.forename: Gordon S
authors.initials: GS
authors.lastname: Doig
authors.forename: Heleen
authors.initials: H
authors.lastname: Oudemans van Straaten
authors.forename: Claudio
authors.initials: C
authors.lastname: Ronco
authors.forename: John A
authors.initials: JA
authors.lastname: Kellum
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis* / Q000628:therapy; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007773:Lactates / Q000097:blood; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012372:ROC Curve; D017582:Renal Replacement Therapy; D012720:Severity of Illness Index
chemical_list: D007773:Lactates