Data Sources—Agency for Healthcare Research and Quality (AHRQ)
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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.
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:
- 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 data set. Weights are used to develop national estimates. 2004 NIS contains data for more than 8 million discharges from 1,004 hospitals located in 37 States, approximating a 20 percent stratified sample of U.S. community hospitals.
- The 2004 HCUP Statewide Inpatient Databases (SID) include all hospitals (with all of their discharges) from 37 participating States. In aggregate, the SID represents approximately 90 percent of all U.S. hospital discharges, totaling nearly 32 million inpatient discharge abstracts.
Disparities Analysis File
A special disparities analysis file (DAF) was created from SID data to provide national estimates for the National Healthcare Disparities Report (NHDR). It consists of weighted records from a sample of hospitals from 23 States participating in HCUP that have high-quality race/ethnicity data: AZ, AR, CA, CO, CT, FL, GA, HI, KS, MD, MA, MI, MO, NH, NJ, NY, RI, SC, TN, TX, VA, VT, and WI. In 2004, the 23 States accounted for 60 percent of U.S. hospital discharges (based on the American Hospital Association annual survey), about 60 percent of Whites and African Americans in the Nation and about 80 percent of Asians and Pacific Islanders and Hispanics.
The HCUP databases maintain the combined categorization of race/ethnicity categories, resulting in the categories of Hispanic of all races and non-Hispanic African Americans, Asian and Pacific Islanders, and Whites. Not all States collect race and ethnicity data uniformly; when a State and its hospitals collect Hispanic ethnicity separately from race, HCUP uses Hispanic ethnicity to override any other race category.
Community hospitals from the 23 States were sampled to approximate a 40 percent stratified sample of U.S. community hospitals, with stratification based on 5 hospital characteristics: geographic region, hospital ownership, urbanized location, teaching status, and bed size. Hospitals were excluded from the sampling frame if the coding of patient race was suspect. Once the 40 percent sample was drawn, discharge-level weights were developed to produce national-level estimates when applied to the DAF. The final DAF included about 14.7 million hospital discharges from almost 1,800 hospitals. The DAF used the same sampling and weighing strategy used for the NIS, except for the differences described here. The DAF used the same imputation procedures as described for the NIS for race/ethnicity data as well as for missing age, sex, ZIP code, and payer data.
The HCUP NIS and SID contain more than 100 clinical and nonclinical data variables, including age, sex, race, ethnicity, length of stay, discharge status, source of payment, total charges, hospital size, ownership, region, teaching status, diagnoses, and procedures.
Some NHQR and NHDR measures that use HCUP data are based on AHRQ Quality Indicators (QIs), a set of algorithms that may be applied to hospital administrative data to quantify quality issues among inpatient populations. There are four QI categories:
- Inpatient Quality Indicators (IQIs), reflect quality of care in hospitals and currently include 15 mortality indicators for conditions or procedures for which mortality can vary from hospital to hospital; 11 utilization indicators for procedures for which utilization varies across hospitals or geographic areas; and 6 volume indicators for procedures for which outcomes may be related to the volume of procedures performed.
- Prevention Quality Indicators (PQIs) identify hospital admissions for 14 ambulatory care-sensitive conditions, which evidence suggests could have been avoided, in part, through high-quality outpatient care.
- Patient Safety Indicators (PSIs) reflect potential inpatient complications and other patient safety concerns following surgeries, other procedures, and childbirth. There are 27 measures in the most recent version of the PSI software.
- Pediatric Quality Indicators (PDIs) examine 18 conditions that pediatric patients experience within the health care system that may be preventable by changes at the system or provider level. In earlier versions of the QI software, some PDI measures were part of the IQI, PSI, and PQI modules.
Any person, U.S. citizen or foreign, using non-Federal, nonrehabilitation, community hospitals in the United States as defined by the American Hospital Association (AHA).
The AHA defines community hospitals 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, nonrehabilitation hospitals in the AHA Annual Survey of Hospitals.
Age, sex, race, insurance coverage, median household income of the patient's ZIP Code, urbanized location, and region of the United States.
National, four U.S. Census Bureau regions, and States levels (for States participating in SID).
Agency home page: http://www.ahrq.gov.
Data system home page: http://www.ahrq.gov/data/hcup.
AHRQ Quality Indicators: http://www.qualityindicators.ahrq.gov.
- Use of AHRQ Quality Indicator Software in Generating NHQR Tables
The following AHRQ QI software versions were used for generating the HCUP tables in the NHQR and NHDR: IQI Version 3.0; PQI Version 3.0; PSI Version 3.0; and PDI Version 3.0b. For more information, see the methods section for each quality report, available at http://www.innovations.ahrq.gov/.
For detailed information about each measure, see the individual guides to the quality indicators listed below, available from the archives at http://www.qualityindicators.ahrq.gov.
- Inpatient Quality Indicators (IQI)
AHRQ Quality Indicators—Guide to Inpatient Quality Indicators: Quality of Care in Hospitals—Volume, Mortality, and Utilization, Version 3.0. Rockville, MD: Agency for Healthcare Research and Quality, 2006.
- Prevention Quality Indicators (PQI)
AHRQ Quality Indicators—Guide to Prevention Quality Indicators: Hospital Admission for Ambulatory Care Sensitive Conditions, Version 3.0a. Rockville, MD: Agency for Healthcare Research and Quality, 2006.
- Patient Safety Indicators (PSI)
AHRQ Quality Indicators—Guide to Patient Safety Indicators, Version 3.0. Rockville, MD: Agency for Healthcare Research and Quality, 2006.
- Pediatric Quality Indicators (PDI)
AHRQ Quality Indicators—Guide to Pediatric Quality Indicators, Version 3.0b. Rockville, MD: Agency for Healthcare Research and Quality, 2006.
Sources of HCUP Data
Arizona Department of Health Services
Arkansas Department of Health and Human Services
California Office of Statewide Health Planning and Development
Colorado Hospital Association
Connecticut CHIME, Inc.
Florida Agency for Health Care Administration
Georgia Hospital Association
Hawaii Health Information Corporation
Illinois Department of Public Health
Indiana Hospital and Health Association
Iowa Hospital Association
Kansas Hospital Association
Kentucky Cabinet for Health and Family Services
Maryland Health Services Cost Review Commission
Massachusetts Division of Health Care Finance and Policy
Michigan Health and 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 and Human Services
New Jersey Department of Health and Senior Services
New York State Department of Health
North Carolina Department of Health and Human Services
Ohio Hospital Association
Oregon Association of Hospitals and Health Systems
Rhode Island Department of Health
South Carolina State Budget and Control Board
South Dakota Association of Healthcare Organizations
Tennessee Hospital Association
Texas Department of State Health Services
Utah Department of Health, Office of Health Care Statistics
Vermont Association of Hospitals and Health Systems
Virginia Health Information
Washington State Department of Health
West Virginia Health Care Authority
Wisconsin Department of Health and Family Services
State sources listed above may not participate in all years or in all HCUP databases.
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Medical Expenditure Panel Survey (MEPS)
U.S. Department of Health and Human Services, Agency for Healthcare Research and Quality (AHRQ); and Centers for Disease Control and Prevention (CDC), National Center for Health Statistics (NCHS).
Mode of Administration
MEPS comprises three component surveys: the Household Component (HC), the Medical Provider Component (MPC), and the Insurance Component (IC). The MEPS HC, the core survey, is an interviewer-administered CAPI (computer-assisted personal interview) household survey. The data for the NHQR and NHDR are primarily from the following sections of the 2000 and 2003 MEPS HC:
- Self-Administered Questionnaire (SAQ)
This self-administered paper questionnaire collects a variety of health and health care quality measures of adults. The health care quality measures in the SAQ were taken from the health plan version of CAHPS, an AHRQ-sponsored family of survey instruments designed to measure quality of care from the consumer's perspective.
- Diabetes Care Survey (DCS)
This self-administered paper questionnaire, given to people identified as ever having had diabetes, asks about their diabetes care.
- Child Health and Preventive Care (CHPR) section
Starting in 2001, a Child Health and Preventive Care section was added to the MEPS HC interviews during the second half of the year. It included health care quality measures taken from the health plan version of CAHPS®; the Children With Special Health Care Needs screener questions; children's general health status as measured by several questions from the General Health Subscale of the Child Health Questionnaire; Columbia Impairment Scale questions about possible child behavioral problems; and child preventive care questions. The CAHPS® questions and the Children With Special Health Care Needs Screener questions had been in the Parent-Administered Questionnaire (PAQ) in 2000. The PAQ estimates for 2000 may not be completely comparable to the CHPR estimates in later years due to differences in the administration of the PAQ and the CHPR section (parent self-administered paper questionnaire for the PAQ vs. interviewer-administered in-person household interview of household respondent for the CHPR).
- 2000 Parent-Administered Questionnaire (PAQ)
A parent self-administered questionnaire designed to collect a variety of health status and health care quality measures of children from CAHPS® and from the Children With Special Health Care Needs screener. Starting in 2001, a Child Health and Preventive Care section, containing questions that had been in the 2000 PAQ, was added to the MEPS interviews.
- Access to Care (AC)
The AC section of the MEPS-HC gathers information on five main topic areas: family members' origins and preferred languages; family members' usual source of health care; characteristics of usual source of health care providers; satisfaction with and access to the usual source of health care provider; and access to medical treatment, dental treatment, and prescription medicines.
- Preventive Care (PC)
For each person, a series of questions was asked primarily about the receipt of preventive care or screening examinations.
Survey Sample Design
The sampling frame for the MEPS HC is drawn from respondents to the National Health Interview Survey (NHIS), conducted by the National Center for Health Statistics (NCHS). The MEPS HC augments NHIS by selecting a sample of NHIS respondents, collecting additional data on their health care expenditures, and linking these data with additional information from the respondents' medical providers, employers, and insurance providers.
Primary Survey Content
The MEPS-HC collects detailed data on demographic characteristics, health conditions, health status, use of medical care services, charges and payments, access to care, satisfaction with care, health insurance coverage, income, and employment.
Like the NHIS population from which its subpopulation is drawn, the MEPS-HC is a nationally representative survey of the U.S. civilian noninstitutionalized population.
The MEPS-HC collects data on demographic characteristics, including age, sex, race, ethnicity, education, industry and occupation, employment status, household composition, and family income. Race and ethnicity variables and categories changed in 2002 to be compliant with Office of Management and Budget (OMB) standards that required changes by 2003.
The Residence Location categories are based on 2003 urban influence codes. These codes form a 12-part county codification scheme for classifying standard OMB metropolitan counties by size, and nonmetropolitan counties by size of the largest city or town as well as proximity to metropolitan and micropolitan areas. Nonmetropolitan areas are divided into micropolitan and noncore areas.
For some tables, the categories Noncore-adjacent and Noncore-not adjacent were collapsed to the single category Noncore in order to generate statistically reliable estimates. Note that Noncore-not adjacent includes noncore counties adjacent to micropolitan areas that do not have their own town.
For more information on urban influence codes, go to
1996 to present.
National. The HC data also can be shown for the four U.S. Census Bureau regions (Northeast, Midwest, South, and West), as well as Residence Location status.
AHRQ fields a new MEPS panel each year. In this design, 2 calendar years of information are collected from each household in a series of 5 rounds of data collection over a 2½-year period. These data are then linked with additional information collected from the respondents' medical providers, employers, and insurance providers. This series of data collection activities is repeated each year on a new sample of households, resulting in overlapping panels of survey data.
Some MEPS, NHIS, and NVSS tables report metropolitan statistical areas, based on the 2000 OMB standards for defining metropolitan and micropolitan areas and on the 2000 Census, as defined below:
Large Central—Central counties in metro areas of 1 million or more population
Large Fringe—Outlying counties in metro areas of 1 million or more population
Medium—Counties in metro areas of 250,000-999,999 population
Small—Counties in metro area of 50,000-249,999 population
Micropolitan—Counties in an area with an urban cluster of 10,000-49,999 population
Estimates in the tables appendix based on MEPS data are suppressed if the unweighted cell value is less than 100. Estimates are flagged if the relative standard error is greater than 30 percent.
Agency home page: http://www.ahrq.gov.
Data system home page: http://www.meps.ahrq.gov.
Cohen J. Design and Methods of the Medical Expenditure Panel Survey Household Component. MEPS Methodology Report No. 1. AHCPR Pub. No. 97-0026. Rockville, MD: AHCPR, 1997.
Cohen S. Sample Design of the 1996 Medical Expenditure Panel Survey Household Component. MEPS Methodology Report No. 2. AHCPR Pub. No. 97-0027. Rockville, MD: AHCPR, 1997.
Cohen JW, Monheit AC, Beauregard KM, et al. The Medical Expenditure Panel Survey: A National Health Information Resource. Inquiry 33:373-389, 1996/1997. Also available as AHCPR Pub. No. 97-R043. Washington, DC: AHCPR, 1997.
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National CAHPS® Benchmarking Database (NCBD)
U.S. Department of Health and Human Services, Agency for Healthcare Research and Quality (AHRQ) in association with a consortium of public and private organizations.
Mode of Administration
By responding to a standardized set of questions administered through a mail or telephone questionnaire, health plan members report on their experiences and rate their health plans and providers in several areas. Participation in the CAHPS® Database is voluntary.
Survey Sample Design
The Health Plan Survey Component is the foundation of the National CAHPS® Benchmarking Database. CAHPS® surveys are administered to a random sample of health plan members by independent survey vendors, following standardized procedures. Since 1998, health plans, purchaser groups, State organizations, and others have participated in this component.
The CAHPS® Hospital Survey (HCAHPS) is also a component of the NCBD. Go to the separate HCAHPS® entry for further information.
Primary Survey Content
Consumer experiences in obtaining health care, including the following five major areas: ability to get needed care; waiting time for care; communication skills of doctors; courtesy and helpfulness of office staff and customer service.
CAHPS® has specific populations for specific surveys and databases, such as adults, children, children with chronic conditions, commercial, Medicaid, and Medicare or Medicare managed care. For more information, check specific table and measure specification information.
Estimates for tables based on CAHPS® data were calculated using plan-level weights; i.e., all respondents in a plan received the same weight. Further, all plans within a State were weighted to contribute equally to the State-level statistic.
The primary purpose of the NCBD is to facilitate comparisons of CAHPS® survey results by survey sponsors. By compiling survey results from a variety of sponsors in a single national database, the NCBD enables participants to compare their own results to relevant benchmarks. The NCBD also offers an important source of primary data for specialized research related to consumer assessments of quality as measured by CAHPS.
The CAHPS® Health Plan Survey database holds 9 years of survey data, representing more than 2.9 million survey respondents; the 2006 database contains survey results for approximately 328,000 adults and children enrolled in commercial, Medicaid, SCHIP, and Medicare plans.
Age, sex, education, race, ethnicity, region, insurance coverage, and health status.
Since 1998. The database currently contains CAHPS® Health Plan Survey data from 1998 to present; the CAHPS® Hospital Survey includes data from 2005 to present.
State, four U.S. Census Bureau regions.
Agency home page: https://www.cahps.ahrq.gov/default.asp.
Data system home page: http://www.cahps.ahrq.gov/content/ncbd/ncbd_Intro.asp.
National CAHPS® Benchmarking Database. 2006 CAHPS® Health Plan Survey Chartbook: What Consumers Say About Their Experiences With Their Health Plans and Medical Care. Rockville, MD: Agency for Healthcare Research and Quality, September 2006.
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