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Comparison between SAPS II and SAPS 3 in predicting hospital mortality in a cohort of 103 Italian ICUs. Is new always better?

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More recent severity scores should be more reliable than older ones because they account for the improvement in medical care over time. To provide more insight into this issue, we compared the predictive ability of the Simplified Acute Physiology Score (SAPS) II and SAPS 3 (originally developed from data collected in 1991–1992 and 2002, respectively) on a sample of critically ill patients.


This was a prospective observational study on 3,661 patients from 103 Italian intensive care units. Standardized mortality ratios (SMRs) were calculated. Assessment of calibration across risk classes was performed using the GiViTI calibration belt. Discrimination was evaluated by means of the area under the receiver operating characteristic analysis.


Both scores were shown to discriminate fairly. SAPS 3 largely overpredicted mortality, more than SAPS II (SMR 0.63, 95 % CI 0.60–0.66 vs. 0.87, 95 % CI 0.83–0.91). This result was consistent and statistically significant across all risk classes for SAPS 3. SAPS II did not show relevant deviations from ideal calibration in the first two deciles of risk, whereas in higher-risk classes it overpredicted mortality.


Both scores provided unreliable predictions, but unexpectedly the newer SAPS 3 turned out to overpredict mortality more than the older SAPS II.

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The study was wholly funded by GiViTI-Istituto di Ricerche Farmacologiche Mario Negri, Bergamo (Italy). GiViTI is the recipient of unconditioned grants from Bellco, Brahms, and Astellas, which did not, however, have any role in this study. The authors would like to thank Abramo Anghileri and Michele Giardino (Istituto di Ricerche Farmacologiche Mario Negri) for their contribution in developing and maintaining the data collection software.

Conflicts of interest

The authors declare they have no conflict of interest regarding the content of the manuscript.

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Correspondence to Daniele Poole.

Additional information

This article is discussed in the editorial available at:doi: 10.1007/s00134-012-2579-z.

The complete list of study participants appears in the Appendix.

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Below is the link to the electronic supplementary material.

Supplementary material 1 (DOC 917 kb)



GiViTI steering committee members

Guido Bertolini (Ranica, BG); Daniela Boccalatte (Lucca); Arturo Chieregato (Cesena); Daniela Codazzi (Bari); Roberto Fumagalli (Monza); Giorgio Gambale (Forlì); Martin Langer (Milano); Sergio Livigni (Torino); Paolo Malacarne (Pisa); Giuseppe Nardi (Roma); Daniele Poole (Belluno); Danilo Radrizzani (Legnano, MI); Mario Tavola (Lecco).

List of study participants

Marco Abastanotti (Manerbio—BS), Claudia Acciari (Ascoli Piceno—AP), Annamaria Acquarolo (Brescia—BS), Arnaldo Alberti (Porto Viro—RO), Armando Alborghetti (Ponte San Pietro—BG), Paolo Antolini (Fermo—AP), Enrico Arditi (Genova—GE), Massimo Barattini (Firenze—FI), Arcangelo Bartoccini (Borgomanero—NO), Teresa Bartoli (Antella—FI), Francesco Bassi (Cinisello Balsamo—MI), Eduardo Beck (Desio—MI), Uberto Belloni (Ivrea—TO), Mario Bellorini (Tradate—VA), Cesare Benanti (Pescia—PT), Mara Olga Bernasconi (Rovigo—RO), Andrea Bianchin (Montebelluna—TV), Angelo Blasetti (Avezzano—AQ), Daniela Boccalatte (Lucca—LU), Andrea Bonfà (Prato—PO), Monica Bonfiglio (Lavagna—GE), Cesare Breschi (Pesaro—PU), Emanuela Brunori (Macerata—MC), Roberto Buonanno (Lacco Ameno—NA), Virginio Buzzetti (Orbetello Scalo—GR), Gian Virgilio Cabano (Busto Arsizio—VA), Giuseppe Calicchio (Salerno—SA), Livio Carnevale (Pavia—PV), Lucia Casagrande (Treviso—TV), Pierpaolo Casalini (Faenza—RA), Giacomo Castiglione (Catania—CT), Elena Chinelli (Bologna—BO), Maddalena Coaloa (Savigliano—CN), Riccardo Colombo (Milano—MI), Sergio Colombo (Milano—MI), Walter Corsini (Carrara—MS), Eleonora Costanzo (Asti—AT), Tito Cottignoli (Lugo di Romagna—RA), Luciano Crema (Cremona—CR), Dolores Da Re (Este—PD), Roberto Alberto De Blasi (Roma—RM), Elvio De Blasio (Benevento—BN), Marino Del Ferro (Oderzo—TV), Pierfrancesco Di Masi (Castellana Grotte—BA), Dino Di Pasquale (Pontedera—PI), Ivano Donato (Cantù—CO), Lea Paola Fabbri (Firenze—FI), Emilio Fabbri (Forlì—FC), Maria Cristina Fabi (Fano—PU), Luciana Faccio (Torino—TO), Paolo Febbrari (Brescia—BS), Francesco Ferla (Cefalù—PA), Gilberto Fiore (Moncalieri—TO), Claudio Fogliati (Orbassano—TO), Emiliano Gamberini (Cesena—FC), Alberto Garelli (Ravenna—RA), Massimo Gianni (Aosta—AO), Stefano Giannoni (Empoli—FI), Daniela Giudici (Milano—MI), Pier Mario Giugiaro (Ciriè—TO), Maurizio Greco (Ariano Irpino—AV), Michele Isetta (Genova—GE), Luigi Lacquaniti (Rossano—CS), Sergio Livigni (Torino—TO), Roberto Madonna (Grosseto—GR), Maria Federica Magatti (Como—CO), Paolo Malacarne (Pisa—PI), Alba Malinconi (Este—PD), Stefano Mancosu (Cagliari—CA), Valerio Mangani (Firenze—FI), Giorgio Mantovani (Ferrara—FE), Alessandro Mastroianni (Chieri—TO), Marianna Messina (Olbia—OT), Renzo Miglioranzi (Pieve di Coriano—MN), Salvatore Murru (Cagliari—CA), Giuseppe Nardi (Roma—RM), Giuseppe Natalini (Brescia—BS), Lorenzo Odetto (Orbassano—TO), Carlo Oliviero (Novara—NO), Daniela Maria Pacini (Genova—GE), Giorgio Paganini (Sanremo—IM), Maurizio Palmer (Aversa—CE), Luigi Panella (L’Aquila—AQ), Silvano Papiri (San Benedetto del Tronto—AP), Mauro Pastorelli (Pinerolo—TO), Maurizio Pegoraro (Castelfranco Veneto—TV), Angelo Pezzi (Milano—MI), Donatella Pinciroli (Legnano—MI), Marialuisa Pizzaballa (Zingonia—BG), Maurizio Postiglione (Napoli—NA), Massimo Raffaeli (Milano—MI), Paolo Riverso (Sanremo—IM), Mario Romitti (Piacenza—PC), Nicola Rossi (Monza—MI), Maurizio Rossi (Menaggio—CO), Federica Rottoli (Bergamo—BG), Rosa Salcuni (Ivrea—TO), Monica Savioli (Milano—MI), Silvia Scarrone (Alessandria—AL), Vincenzo Segala (Torino—TO), Pieraurelio Segalini (Piacenza—PC), Alberto Sicignano (Milano—MI), Maria Josè Sucre (Castellammare di Stabia—NA), Claudio Tagliaferri (Piacenza—PC), Romano Tetamo (Palermo—PA), Giuseppe Tibaldi (Brescia—BS), Silvia Tinacci (Fucecchio—FI), Livio Todesco (Cittadella—PD), Gabriele Tomasoni (Manerbio—BS), Mauro Torta (Torino—TO), Carlo Tripepi (Monselice—PD), Pietro Vecchiarelli (Viterbo—VT), Maria Grazia Visconti (Cernusco sul Naviglio—MI), Nicoletta Vivaldi (Alessandria—AL), Giuseppe Angelo Vulcano (Rossano—CS), Sergio Zappa (Brescia—BS), Francesco Zuccaro (Matera—MT).

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Poole, D., Rossi, C., Latronico, N. et al. Comparison between SAPS II and SAPS 3 in predicting hospital mortality in a cohort of 103 Italian ICUs. Is new always better?. Intensive Care Med 38, 1280–1288 (2012).

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