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HCUP databases provide national data on insured and uninsured patients and are easily accessed

The Agency for Healthcare Research and Quality's Healthcare Cost and Utilization Project (HCUP) has evolved over the years into a family of databases that provide multi-State, inpatient and outpatient discharge records on insured and uninsured patients.

HCUP databases include the State Inpatient Databases (SID); the Nationwide Inpatient Sample (NIS); the Kids' Inpatient Database (KID); and the State Ambulatory Surgery Databases (SASD). The HCUP databases are described in a recent article by AHRQ researchers Claudia Steiner, M.D., M.P.H., Anne Elixhauser, Ph.D., and Jenny Schnaier, M.A.

These databases contain clinical and nonclinical data ranging from a patient's age and sex, medical conditions, and procedures the patient received, to length and cost of hospital stay and who will pay for it. The SID contains each participating State's community hospital inpatient discharge records. The NIS is a 20 percent sample of all U.S. community hospitals that includes about 1,000 hospitals with about 7 million discharge records that are weighted to national estimates. The KID provides data on a sample of patients 18 years and younger discharged from hospitals in all participating States. The SASD includes records from hospital-affiliated ambulatory surgery sites. The collection of emergency department data is currently underway as a pilot activity.

All of these databases facilitate health services research on a variety of topics, such as the use and cost of hospital services, quality assessment, medical treatment variations, diffusion of new medical technology, impact of health policy changes, access to care (inference), small-area variations, and care of special populations.

More details are in "The Healthcare Cost and Utilization Project: An overview," by Drs. Steiner and Elixhauser and Ms. Schnaier, in the May 2002 Effective Clinical Practice 5(3), pp. 143-151.

Reprints (AHRQ Publication No. 02-R085) are available from the AHRQ Publications Clearinghouse.

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