This study compares quality of care measures for hospitals with fully implemented computerized physician order entry (CPOE) systems with hospitals that have not fully implemented such a system. Using a cross-sectional design, this study linked hospital quality data from the Centers for Medicare and Medicaid Services to the Health Information Management Systems Society Analytics database, which contains hospital CPOE adoption information. Performance on quality measures was assessed using univariate and multivariate methods. In all, 8% of hospitals have fully implemented CPOE systems; CPOE hospitals were more frequently larger, not-for-profit, and teaching hospitals. After controlling for confounders, CPOE hospitals outperformed comparison hospitals on 5 of 11 measures related to ordering medications and on 1 of 9 nonmedication-related quality measures. Using a large sample of hospitals, our study found significant positive associations between specific objective quality indicators and CPOE implementation. © 2009 by the American College of Medical Quality.