Healthcare Cost and Utilization Project-State Inpatient Databases
The Healthcare Cost and Utilization Project (HCUP) is a family of health care databases and related software tools developed through a federal-state-industry partnership to build a multistate health data system for health care research and decision making. The State Inpatient Databases (SID), a component of HCUP, is a set of hospital databases from data organizations in participating states. The SID encompasses about 90 % of all U.S. community hospital discharges. Some states include discharges from specialty facilities, such as psychiatric hospitals.
National Center for Health Statistics. Health United States 2009: With Special Feature on Medical Technology. Hyattsville, Maryland. 2010; pp 452-453.
http://www.ahrq.gov/data/hcup and related web pages.