The CPO has many national and local databases available for use with collaborators, including the State Inpatient Database (SID), Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality; National Inpatient Sample (NIS), Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality; the Multicenter Perioperative Outcomes Group (MPOG); the National Anesthesia Clinical Outcomes Registry (NACOR), developed and maintained by the Anesthesia Quality Institute (AQI); and the American College of Surgeons National Surgical Quality Improvement Program; and local data.