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National Healthcare Disparities Report, 2005

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Healthcare Cost and Utilization Project (HCUP)


U.S. Department of Health and Human Services, Agency for Healthcare Research and Quality (AHRQ).

Mode of Collection

HCUP databases bring together the data collection efforts of State government data organizations, hospital associations, private data organizations, and the Federal government to create a national information resource of discharge-level health care data. The number of participating States increased to 36 in 2002. See "Sources of HCUP Data" below.

Sample Design

HCUP includes a collection of longitudinal hospital care data, with all-payer, discharge-level information beginning in 1988. Two HCUP discharge datasets were used in this report: 1) The HCUP Nationwide Inpatient Sample (NIS) is a nationally stratified sample of hospitals (with all of their discharges) from States that contribute data to the NIS dataset. Weights are used to develop national estimates. NIS 2002 contains data for approximately 7 million discharges from 995 hospitals located in 35 States, approximating a 20 percent stratified sample of U.S. community hospitals. 2) The 2002 HCUP Statewide Inpatient Databases (SID) include all hospitals (with all of their discharges) from 36 participating States. In aggregate, the SID represent approximately 90 percent of all U.S. hospital discharges, totaling over 28 million inpatient discharge abstracts.

Primary Content

The HCUP NIS and SID contain over 100 clinical and nonclinical data variables, including age, gender; race; ethnicity; length of stay; discharge status; source of payment; total charges, hospital size, ownership, region, teaching status; diagnoses and procedures.

Some NHDR measures that use HCUP data are based on the following AHRQ Quality Indicators:

  1. Inpatient Quality Indicators (IQI), which reflect quality of care in hospitals, include 13 mortality indicators for conditions or procedures for which mortality can vary from hospital to hospital; 9 utilization indicators for procedures for which utilization varies across hospitals or geographic areas; and 7 volume indicators for procedures for which outcomes may be related to the volume of those procedures performed.
  2. Prevention Quality Indicators (PQI) identify hospital admissions for 16 ambulatory care sensitive conditions, which evidence suggests could have been avoided, in part, through high-quality outpatient care.
  3. Patient Safety Indicators (PSI) reflect potential inpatient complications and other patient safety concerns following surgeries, other procedures, and childbirth.

Population Targeted

Any person, U.S. citizen or foreign, using non-Federal, non-rehabilitation, community hospitals in the United States as defined by the American Hospital Association (AHA).

The AHA defines community hospital as "all non-Federal, short-term, general, and other specialty hospitals, excluding hospital units of institutions." Included among community hospitals are specialty hospitals, such as obstetrics-gynecology, ear-nose-throat, short-term rehabilitation, orthopedic, and pediatric institutions. Also included are public hospitals and academic medical centers. The NIS and analyses of the SID for this report excluded short-term rehabilitation hospitals (beginning with 1998 data), long-term hospitals, psychiatric hospitals, and alcoholism/chemical dependency treatment facilities.

Although not all States participate in the HCUP database, the NIS is weighted to give national estimates using weights based on all U.S. community, non-rehabilitation hospitals in the American Hospital Association Annual Survey of Hospitals.

Demographic Data

Age, gender, race, insurance coverage, median household income of the patient's ZIP Code, urbanized location, and region of the United States.

Years Collected

Since 1988.



Geographic Estimates

National, four U.S. Census Bureau regions, and State levels (for States participating in SID).

Contact Information

Agency homepage:

Data system homepage:

AHRQ Quality Indicators:


  1. Use of AHRQ Quality Indicator Software in Generating NHQR Tables

    The following AHRQ QI software versions were used for generating the HCUP tables in this report: IQI: Version 2.1, revision 3 (July 2004); PQI: Version 2.1, revision 3 (January 2004); PSI: Version 2.1, revision 2 (October 2004). For more information, see the methods section for each quality report, available at

    For detailed information about each measure, see the individual guides to the quality indicators listed below, available from the archives at

  2. Inpatient Quality Indicators [IQI]

    AHRQ Quality Indicators—Guide to Inpatient Quality Indicators: Quality of Care in Hospitals—Volume, Mortality, and Utilization. Rockville, MD: Agency for Healthcare Research and Quality, 2002. Revision 3 (July 21, 2004). AHRQ Pub. No. 02-RO204.

  3. Prevention Quality Indicators [PQI]

    AHRQ Quality Indicators—Guide to Prevention Quality Indicators: Hospital Admission for Ambulatory Care Sensitive Conditions. Rockville, MD: Agency for Healthcare Research and Quality. Revision 3. (January 9, 2004). AHRQ Pub. No. 02-R0203.

  4. Patient Safety Indicators [PSI]

    AHRQ Quality Indicators—Guide to Patient Safety Indicators. Rockville, MD: Agency for Healthcare Research and Quality, 2003. Version 2.1, Revision 2, (October 22, 2004). AHRQ Pub.03-R203.

Sources of HCUP Data

Arizona Department of Health Services

California Office of Statewide Health Planning & Development

Colorado Health & Hospital Association

Connecticut—CHIME, Inc.

Florida Agency for Health Care Administration

Georgia—GHA: An Association of Hospitals & Health Systems

Hawaii Health Information Corporation

Illinois Department of Public Health

Indiana Hospital & Health Association

Iowa Hospital Association

Kansas Hospital Association

Kentucky Department for Public Health

Maine Health Data Organization

Maryland Health Services Cost Review Commission

Massachusetts Division of Health Care Finance and Policy

Michigan Health & Hospital Association

Minnesota Hospital Association

Missouri Hospital Industry Data Institute

Nebraska Hospital Association

Nevada Department of Human Resources, Center for Health Information Analysis

New Hampshire Department of Health & Human Services

New Jersey Department of Health & Senior Services

New York State Department of Health

North Carolina Department of Health and Human Services

Ohio Hospital Association

Oregon Association of Hospitals & Health Systems

Pennsylvania Health Care Cost Containment Council

Rhode Island Department of Health

South Carolina State Budget & Control Board

South Dakota Association of Healthcare Organizations

Tennessee Hospital Association

Texas Department of State Health Services

Utah Department of Health

Vermont Association of Hospitals and Health Systems

Virginia Health Information

Washington State Department of Health

West Virginia Health Care Authority

Wisconsin Department of Health & Family Services



The information on this page is archived and provided for reference purposes only.


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