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SAPS II revisited

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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).

Design and setting

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.


33,471 patients treated between 1999 and 2000.

Measurements and 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.


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.

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The authors thank the members of 25 ICUs of Cub-Rea for providing support. Reviewers are acknowledged for their constructive comments. This work was partly presented at the 16th Annual Congress of the European Society of Intensive Care Medicine in Amsterdam, 5–8 October 2003 [13].

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Corresponding author

Correspondence to Bertrand Guidet.

Additional information

This research was financed by The Clinical Research Program of the French Ministry of Health (PHRC AOM 98-124). ICUs participating in the study are listed in the Appendix

Electronic Supplementary Material

Appendix: members of the CUB-REA database

Appendix: members of the CUB-REA database

F. Jardin, B Page (Hôpital Ambroise Paré), J.P. Bedos, P. Guezennec (Hôpital André Mignot), F. Brivet (Hôpital Antoine Béclère), Y. Cohen, J.P. Fosse (Hôpital Avicenne), C.l. Gibert, B. Regnier, P. Auburtin (Hôpital Bichat), C. Richard, J. Depré-Vassal (Hôpital Bicêtre), J. Labrousse, E. Guerot (Hôpital Boucicaut), J.Y. Fagon (Hôpital Européen Georges Pompidou), J.F. Dhainaut, A. Cariou (Hôpital Cochin), F. Fraisse, G. Moret (Hôpital Delafontaine), P. Kalfon (Hôpital Diaconesses), F. Blin (Hôpital Gonesse), F. Lemaire, C. Brun-Buisson (Hôpital Henri Mondor), A. Rabbat (Hôpital Hotel Dieu), G. Nitenberg, F. Blot (Institut Gustave Roussy), J.L. Pourriat, R. Gauzit (Hôpital Jean Verdier), F. Baud, D. Goldgran-Toledano (Hôpital Lariboisière), D. Dreyfuss (Hôpital Louis Mourier), A. Tenaillon (Hôpital Louise Michel), J.L. Pallot, E. Obadia (Hôpital Montreuil), J.M. Coulaud, L. Donetti (Hôpital Montfermeil), H. Bismuth (Hôpital Paul Brousse), T. Similowski (Hôpital Pitié-Salpétrière), F. Bolgert (Hôpital Pitié-Salpétrière, H. Outin (Medical ICU, Hôpital Poissy/St. Germain), J.P. Terville (Surgical ICU, Hôpital Poissy/St. Germain), P. Gajdos, M.C. Jars-Guincestre (Hôpital Raymond Poincaré), F. Hilpert, P. Manet (Hôpital Robert Ballanger), G. Offenstadt, B. Guidet (Hôpital Saint-Antoine), J. Carlet, B. Misset (Hôpital Saint-Joseph), J.R. Le Gall, G. Leleu (Medical ICU, Hôpital Saint-Louis), L. Jacob (Surgical ICU, Hôpital Saint-Louis), C. Mayaud, A. Parrot (Hôpital Tenon), G. Bleichner, H. Mentec (Hôpital Victor Dupouy).

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Aegerter, P., Boumendil, A., Retbi, A. et al. SAPS II revisited. Intensive Care Med 31, 416–423 (2005).

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