Objective: To assess which adverse postsurgical outcomes are best predicted by the Study on the Efficacy of Nosocomial Infection Control (SENIC) index and the National Nosocomial Infection Surveillance system (NNIS) index.
Design: Prospective cohort study.
Setting: The service of general surgery at a tertiary care hospital.
Patients: A consecutive series of patients hospitalized for more than 1 day (n=2,989).
Results: The outcome best predicted by the SENIC and NNIS indices was assessed by estimating the area under the receiver operating characteristic (ROC) curve. The areas under the ROC curves for nosocomial infection and in-hospital death were higher for the NNIS index than they were for the SENIC index (P<.05). The NNIS index predicted in-hospital death better than it predicted surgical site infection (area under the ROC curve+/-SE, 0.836+/-0.022 vs 0.689+/-0.017; P=.001).
Conclusions: The NNIS index is superior to the SENIC index for all adverse postsurgical outcomes. Its ability to predict in-hospital mortality is clearly better than its ability to predict surgical site infection.