title: SAPS II revisited.
abstract: OBJECTIVE
  To construct and validate an update of the Simplified Acute Physiology Score II (SAPS II) for the evaluation of clinical performance of Intensive Care Units (ICU).
  
  
  METHODS
  Retrospective analysis of prospectively collected multicenter data in 32 ICUs located in the Paris area belonging to the Cub-Rea database and participating in a performance evaluation project.
  
  
  METHODS
  33,471 patients treated between 1999 and 2000.
  
  
  RESULTS
  Two logistic regression models based on SAPS II were developed to estimate in-hospital mortality among ICU patients. The second model comprised reevaluation of original items of SAPS II and integration of the preadmission location and chronic comorbidity. Internal and external validation were performed. In the two validation samples the most complex model had better calibration than the original SAPS II for in-hospital mortality but its discrimination was not significantly higher (area under ROC curve 0.89 vs. 0.87 for SAPS II). Second-level customization and integration of new items improved uniformity of fit for various categories of patients except for diagnosis-related groups. The rank order of ICUs was modified according to the model used.
  
  
  CONCLUSIONS
  The overall performance of SAPS II derived models was good, even in the context of a community cohort and routinely gathered data. However, one-half the variation of outcome remains unexplained after controlling for admission characteristics, and uniformity of prediction across diagnostic subgroups was not achieved. Differences in case-mix still limit comparisons of quality of care.
authors.affiliation: Department of Biostatistics, Hôpital Ambroise Paré, Assistance Publique Hôpitaux de Paris, Boulogne, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Aegerter
authors.forename: Ariane
authors.initials: A
authors.lastname: Boumendil
authors.forename: Aurélia
authors.initials: A
authors.lastname: Retbi
authors.forename: Etienne
authors.initials: E
authors.lastname: Minvielle
authors.forename: Benoit
authors.initials: B
authors.lastname: Dervaux
authors.forename: Bertrand
authors.initials: B
authors.lastname: Guidet
mesh_terms: D018806:APACHE; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005602:France; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D017063:Outcome Assessment, Health Care / Q000379:methods*; D000091402:Prohibitins; D012372:ROC Curve; D012720:Severity of Illness Index