title: The predictive performance of the SAPS II and SAPS 3 scoring systems: A retrospective analysis.
abstract: The purpose was to analyze and compare the performance of Simplified Acute Physiology Score (SAPS) II and SAPS 3 (North Europe Logit) in an intensive care unit (ICU) for internal disorders at a German university hospital.
  
  
  
  This retrospective study was conducted at a single-center 12-bed ICU sector for Internal Medicine in Essen, Germany, within an 18-month period. Data for adult ICU patients (N = 548) were evaluated. SAPS II and SAPS 3 scores were assessed along with the predicted mortality rates. Discrimination was evaluated by calculating the area under the receiver operating characteristic curve, and calibration was evaluated using the Hosmer-Lemeshow goodness-of-fit C-test. The ratios of observed-to-expected deaths (standardized mortality ratio, SMR) were calculated along with the 95% confidence intervals (95% CIs).
  
  
  
  The in-hospital mortality rate was 22.6%, which provided an SMR of 0.91 (95% CI, 0.77-0.99) for SAPS II and 0.62 (95% CI, 0.52-0.71) for SAPS 3. Both SAPS II and SAPS 3 exhibited acceptable discrimination, with an area under the receiver operating characteristic curve of 0.84 (95% CI, 0.79-0.89) and 0.73 (95% CI, 0.67-0.79), respectively. However, SAPS II demonstrated superior SMR-based discrimination, which was closer to the observed mortality rate, compared with SAPS 3. Calibration curves exhibited similar performance based on the Hosmer-Lemeshow goodness-of-fit C-test results: χ(2) = 7.10 with P = .525 for SAPS II and χ(2) = 3.10 with P = .876 for SAPS 3. Interestingly, both scores overpredicted mortality.
  
  
  
  In this study, SAPS 3 overestimated mortality and therefore appears less suitable for risk evaluation in comparison to SAPS II.
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital Essen, Essen, Germany. Electronic address: antonios.katsounas@uk-essen.de.
authors.forename: Antonios
authors.initials: A
authors.lastname: Katsounas
authors.affiliation: Department of Cardiology, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany.
authors.forename: Ilina
authors.initials: I
authors.lastname: Kamacharova
authors.affiliation: Department of Nephrology, University Hospital Essen, Essen, Germany.
authors.forename: Bartosz
authors.initials: B
authors.lastname: Tyczynski
authors.affiliation: Cardioangiological Center Bethanien (CCB), Frankfurt, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Eggebrecht
authors.affiliation: Institute of Medical Informatics, Biometrics and Epidemiology, University Hospital Essen, Essen, Germany.
authors.forename: Raimund
authors.initials: R
authors.lastname: Erbel
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital Essen, Essen, Germany.
authors.forename: Ali
authors.initials: A
authors.lastname: Canbay
authors.affiliation: Department of Gastroenterology and Hepatology, University Hospital Essen, Essen, Germany.
authors.forename: Guido
authors.initials: G
authors.lastname: Gerken
authors.affiliation: Department of Cardiology, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany.
authors.forename: Tienush
authors.initials: T
authors.lastname: Rassaf
authors.affiliation: Department of Cardiology, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany.
authors.forename: Rolf Alexander
authors.initials: RA
authors.lastname: Jánosi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003422:Critical Care; D016638:Critical Illness / Q000401:mortality*; D005260:Female; D005858:Germany; D017052:Hospital Mortality; D006785:Hospitals, University; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D000072878:Simplified Acute Physiology Score; D055815:Young Adult
keywords: Critical care; ICU; Mortality; SAPS 3; SAPS II