- Study 3. The impact of CRE infection on mortality, length of stay, cost, length of hospital and ICU stay, and length of mechanical ventilation of patients will be assessed by comparison with those of CSE infection and admitted patients. All time-to-event outcomes (for costs and extra hospital/ICU days see below) will be compared using survival techniques. Because the outcome infection due to CRE is subject to the competing risks of death in hospital w/o CRE infection and discharged alive from hospital with or without CRE infection, the analyses shall be supplemented by those of the competing outcomes. Goodness of fit will be assessed throughout. Extra hospital/ICU days will be estimated using the multistate approach of Beyersmann et al. Variable selection will be based on Akaike's information criterion. Goodness of fit will be assessed throughout.