ObjectiveTo compare the survival of patients in a teaching hospital pediatric intensive care unit in which residents provided after-hours in-house coverage with survival in the same unit with hospitalists providing this coverage.DesignRetrospective cohort study.SettingPediatric intensive care units in two teaching hospitals that are managed by the same group of academic pediatric intensivists, one of which transitioned from the traditional resident-staffed model to a hospitalist-staffed model for after-hours in-house coverage.PatientsAll pediatric patients admitted to the study pediatric intensive care unit and to the control pediatric intensive care unit from April 1997 through March 1998, the resident era, and from October 1998 through September 1999, the hospitalist era.InterventionsMultivariate analysis, with survival as the dependent variable and era (hospitalist vs. resident) as an independent variable, was used to compare odds of survival during the hospitalist era with that of the resident era, adjusted for severity of illness. Multivariate linear regression was used to compare length of stay during the hospitalist era with that of the resident era, adjusted for severity of illness. Pediatric Risk of Mortality scores and those diagnostic categories typically associated with higher mortality rates also were included as independent variables in both analyses to adjust for severity of illness.Measurements and Main ResultsMultivariate analysis yielded an estimated odds ratio of survival of 2.8 for the hospitalist era compared with the resident era (p= .013), and our analysis supported an independent association between survival and hospitalist era. Multivariate linear regression showed that length of stay, also adjusted for severity of illness, during the hospitalist era was 21.1 hrs shorter than during the resident era (p= .013). Neither survival nor length of stay was significantly associated with era at the control hospital.ConclusionImproved survival with hospitalists, rather than residents, providing after-hours care when an intensivist is not in house suggests that the quality of care of critically ill patients is improved when more experienced physicians are providing bedside care. Shorter length of stay with the hospitalist model also may reflect improved quality of care.