The healthcare cost and utilization project: an overview.

DATABASE . Healthcare Cost and Utilization Project (HCUP)-a family of databases including the State Inpatient Databases (SID), the Nationwide Inpatient Sample (NIS), the Kids' Inpatient Database (KID), and the outpatient databases State Ambulatory Surgery Data (SASD) and State Emergency Department Data (SEDD). DESCRIPTION Multistate, inpatient (SID, NIS, KID) and outpatient (SASD, SEDD) discharge records on insured and uninsured patients. SOURCE Partnership between the Agency for Healthcare Research and Quality (AHRQ) and public and private statewide data organizations. AVAILABLE DATA: Selected data elements from inpatient and outpatient discharge records, including patient demographic, clinical, disposition and diagnostic/procedural information; hospital identification (ID); facility charges; and other facility information. DATA YEARS AVAILABLE: Varies by database: NIS 1988-2000; SID 1995-2000; KID 1997 and 2000; SASD 1995-2000; and SEDD in pilot phase. Future data years anticipated for all datasets and back years for SID and SASD. UNITS OF ANALYSIS: Patient (in states with encrypted patient identification), physician, market, and state. RESEARCH QUESTIONS Quality assessment, use and cost of hospital services, medical treatment variations, use of ambulatory surgery services, diffusion of medical technology, impact of health policy changes, access to care (inference), study of rare illness or procedures, small area variations, and care of special populations. STRENGTHS: Largest collection of all-payer, uniform, state-based inpatient and ambulatory surgery administrative data. LIMITATIONS Lacks clinical detail (e.g., stage of disease, vital statistics) and laboratory and pharmacy data. Ability to track patients across time and setting varies by state. ACCESS TO DATA Access available to all users who sign and abide by the Data Use Agreement. Application kits available at www.ahrq.gov/data/hcup. HCUPnet, an on-line interactive query tool, allows access to data without purchase (www.ahrq. gov/data/hcup/hcupnet.htm).