The Healthcare Cost and Utilization Project (HCUP) National Inpatient Sample (NIS) is the largest publicly available all-payer inpatient care database in the United States. The NIS is designed to produce U.S. regional and national estimates of inpatient utilization, access, cost, quality, and outcomes. Unweighted, it contains data from more than 7 million hospital stays each year. Weighted, it estimates more than 35 million hospitalizations nationally. Developed through a Federal-State-Industry partnership sponsored by the Agency for Healthcare Research and Quality (AHRQ), HCUP data inform decision making at the national, State, and community levels.

Starting with the 2012 data year, the NIS is a sample of discharges from all hospitals participating in HCUP, covering more than 97 percent of the U.S. population. For prior years, the NIS was a sample of hospitals. The NIS allows for weighted national estimates to identify, track, and analyze national trends in health care utilization, access, charges, quality, and outcomes. The NIS's large sample size enables analyses of rare conditions, such as congenital anomalies; uncommon treatments, such as organ transplantation; and special patient populations, such as the uninsured. NIS data are available since 1988, allowing analysis of trends over time.

The NIS inpatient data include clinical and resource use information typically available from discharge abstracts with safeguards to protect the privacy of individual patients, physicians, and hospitals (as required by data sources). Data elements include but are not limited to: diagnoses, procedures, discharge status, patient demographics (e.g., gender, age), total charges, length of stay, and expected payment source, including but not limited to Medicare, Medicaid, private insurance, self-pay, or those billed as ‘no charge’. The NIS excludes data elements that could directly or indirectly identify individuals.

Restricted access data files are available with a data use agreement and brief online security training.

The National Health and Nutrition Examination Survey (NHANES) is designed to assess the health and nutritional status of adults and children in the United States. The survey is unique in that it combines interviews with standardized physical examinations and laboratory tests.

NHANES was conducted on a periodic basis from 1971 to 1994. In 1999 NHANES became continuous. Every year, approximately 5,000 people of all ages are interviewed in their homes and complete the health examination conducted in a mobile examination center.

The NHANES interview includes demographic, socioeconomic, dietary, and health-related questions. The examination component consists of medical, dental, and physiological measurements, as well as the collection of biospecimens, such as blood and urine for laboratory testing.

This set of restricted data contains indirect identifying and/or sensitive information collected in continuous NHANES since 1999. Please refer to the links below for additional data available from NHANES:

• NHANES Public Use Data at: https://wwwn.cdc.gov/nchs/nhanes/Default.aspx


• NHANES Genetic Restricted Data at: https://data.cdc.gov/dataset/National-Health-and-Nutrition-Examination-Survey-N/hdx4-e4uu


• NHANES Restricted Data: Prior to 1999 at: https://data.cdc.gov/dataset/National-Health-and-Nutrition-Examination-Survey-N/ic32-yq9m


• NHANES National Youth Fitness Survey (NNYFS) Restricted Data at: https://data.cdc.gov/dataset/3-NHANES-National-Youth-Fitness-Survey-NNYFS-Restr/5u84-m4rs

Please refer to the NHANES Analytic Guidelines at: https://wwwn.cdc.gov/nchs/nhanes/analyticguidelines.aspx and the on-line NHANES Tutorial at: https://wwwn.cdc.gov/nchs/nhanes/tutorials/default.aspx for further details on the survey design, implementation, and data analysis.

DNA samples were collected in the Third National Health and Nutrition Examination Survey (NHANES III; 1988-1994) and in subsequent NHANES cycles (1999-2002, 2007-2008, 2009-2010, and 2011-2012). The program is a nationally representative collection of stored DNA samples and genetic data and will serve to add to the extensive amount of health, nutritional, and environmental information collected from NHANES. Resulting genetic variants are deposited into the NHANES Genetic Data Repository. These datasets are categorized as restricted data since they contain identifiable information.

For more information on the NHANES Genetic Data please visit: NHANES DNA Specimens and Genetic Data Program at: https://www.cdc.gov/nchs/nhanes/biospecimens/dnaspecimens.htm.
For more information on NHANES, visit the NHANES - National Health and Nutrition Examination Survey Homepage at: https://www.cdc.gov/nchs/nhanes/index.htm.

The National Health and Nutrition Examination Survey (NHANES) is designed to assess the health and nutritional status of adults and children in the United States. The survey is unique in that it combines interviews with standardized physical examinations and laboratory tests.

NHANES was conducted on a periodic basis from 1971 to 1994, including NHANES I (1971-1975), NHANES II (1976-1980), NHANES III (1988-1994), and a Hispanic Health and Nutrition Examination Survey (HHANES, 1982-1984). In 1999, NHANES became continuous and has been collecting data annually ever since.

All of the NHANES programs utilized a stratified, multistage probability cluster design to provide a nationally representative sample of the U.S. civilian, noninstitutionalized population. The NHANES interview includes demographic, socioeconomic, dietary, and health-related questions. The examination component conducted in a mobile examination center consists of medical, dental, and physiological measurements, as well as the collection of biospecimens, such as blood and urine for laboratory testing.

This set of restricted data contains indirect identifying and/or sensitive information collected in NHANES prior to 1999. Please refer to the links below for additional data available from NHANES:

• NHANES Public Use Data at: https://wwwn.cdc.gov/nchs/nhanes/Default.aspx


• NHANES Restricted Data: 1999 - present at: https://data.cdc.gov/dataset/National-Health-and-Nutrition-Examination-Survey-N/9ixb-fwvy


• NHANES Genetic Restricted Data at: https://data.cdc.gov/dataset/National-Health-and-Nutrition-Examination-Survey-N/hdx4-e4uu


• NHANES National Youth Fitness Survey (NNYFS) Restricted Data at: https://data.cdc.gov/dataset/3-NHANES-National-Youth-Fitness-Survey-NNYFS-Restr/5u84-m4rs

Please refer to the NHANES - National Health and Nutrition Examination Survey Homepage at: https://www.cdc.gov/nchs/nhanes/index.htm for further details on the NHANES design, implementation, and data analysis.

HCUPnet is an online data tool based on data from the Healthcare Cost and Utilization Project (HCUP).

The data tool provides healthcare statistics and information for hospital inpatient and emergency department settings, as well as population-based healthcare data on counties. Users are able to query HCUP data to access detailed or summary statistics on inpatient stays and emergency department visits by patient, hospital, and encounter characteristics. Users are also able to generate tables and graphs on national and regional statistics and trends for community hospitals in the United States.

The Healthcare Cost and Utilization Project (HCUP) State Inpatient Databases (SID) are a set of hospital databases that contain the universe of hospital inpatient discharge abstracts from data organizations in participating States. The data are translated into a uniform format to facilitate multi-State comparisons and analyses. The SID are based on data from short term, acute care, nonfederal hospitals. Some States include discharges from specialty facilities, such as acute psychiatric hospitals. The SID include all patients, regardless of payer and contain clinical and resource use information included in a typical discharge abstract, with safeguards to protect the privacy of individual patients, physicians, and hospitals (as required by data sources). Developed through a Federal-State-Industry partnership sponsored by the Agency for Healthcare Research and Quality (AHRQ), HCUP data inform decision making at the national, State, and community levels.

The SID contain clinical and resource-use information that is included in a typical discharge abstract, with safeguards to protect the privacy of individual patients, physicians, and hospitals (as required by data sources). Data elements include but are not limited to: diagnoses, procedures, admission and discharge status, patient demographics (e.g., gender, age), total charges, length of stay, and expected payment source, including but not limited to Medicare, Medicaid, private insurance, self-pay, or those billed as ‘no charge’. In addition to the core set of uniform data elements common to all SID, some include State-specific data elements. The SID exclude data elements that could directly or indirectly identify individuals. For some States, hospital and county identifiers are included that permit linkage to the American Hospital Association Annual Survey File and county-level data from the Bureau of Health Professions' Area Resource File except in States that do not allow the release of hospital identifiers.

Restricted access data files are available with a data use agreement and brief online security training.

The Healthcare Cost and Utilization Project (HCUP) State Ambulatory Surgery Databases (SASD) contain the universe of hospital-based ambulatory surgery encounters in participating States. The SASD include encounter-level data for ambulatory surgeries and may also include various types of outpatient services such as observation stays, lithotripsy, radiation therapy, imaging, chemotherapy, and labor and delivery. The specific types of ambulatory surgery and outpatient services included in each SASD vary by State and data year. All SASD include data from hospital-owned ambulatory surgery facilities. In addition, some States include data from nonhospital-owned facilities. The data are translated into a uniform format to facilitate multi-State comparisons and analyses. The SASD include all patients in participating settings, regardless of the expected payer including but not limited to Medicare, Medicaid, private insurance, self-pay, or those billed as ‘no charge’. Developed through a Federal-State-Industry partnership sponsored by the Agency for Healthcare Research and Quality (AHRQ), HCUP data inform decision making at the national, State, and community levels.

The SASD contain clinical and resource use information included in a typical discharge abstract, with safeguards to protect the privacy of individual patients, physicians, and facilities (as required by data sources). Data elements include but are not limited to: diagnoses, procedures, admission and discharge status, patient demographics (e.g., gender, age), total charges, and expected payment source. In addition to the core set of uniform data elements common to all SASD, some include State-specific data elements. The SASD exclude data elements that could directly or indirectly identify individuals. For some States, hospital and county identifiers are included that permit linkage to the American Hospital Association Annual Survey File and the Bureau of Health Professions' Area Resource File except in States that do not allow the release of hospital identifiers.

Restricted access data files are available with a data use agreement and brief online security training.

The National Health and Nutrition Examination Survey’s (NHANES) National Youth Fitness Survey (NNYFS) was conducted in 2012 to collect nationally representative data on physical activity and fitness levels for U.S. children and adolescents aged 3-15 years, through household interviews and fitness tests conducted in mobile examination centers.

The NNYFS interview includes demographic, socioeconomic, dietary, and health-related questions. The fitness tests included standardized measurements of core, upper, and lower body muscle strength, and gross motor skills, as well as a measurement of cardiovascular fitness by walking and running on a treadmill. A total of 1,640 children and adolescents aged 3-15 were interviewed and 1,576 were examined.

This set of restricted data files contains indirect identifying and/or sensitive information collected in NNYFS. For NNYFS public use files, please visit NNYFS 2012 at: https://wwwn.cdc.gov/nchs/nhanes/search/nnyfs12.aspx.
For more information on the survey design, implementation, and data analysis, see the NNYFS Analytic Guidelines at: https://www.cdc.gov/nchs/nnyfs/analytic_guidelines.htm.
For more information on NHANES, visit the NHANES - National Health and Nutrition Examination Survey Homepage at: https://www.cdc.gov/nchs/nhanes/index.htm.

The Healthcare Cost and Utilization Project (HCUP) Kids' Inpatient Database (KID) is the largest publicly available all-payer pediatric inpatient care database in the United States, containing data from two to three million hospital stays each year. Its large sample size is ideal for developing national and regional estimates and enables analyses of rare conditions, such as congenital anomalies, as well as uncommon treatments, such as organ transplantation. Developed through a Federal-State-Industry partnership sponsored by the Agency for Healthcare Research and Quality, HCUP data inform decision making at the national, State, and community levels.

The KID is a sample of pediatric discharges from 4,000 U.S. hospitals in the HCUP State Inpatient Databases yielding approximately two to three million unweighted hospital discharges for newborns, children, and adolescents per year. About 10 percent of normal newborns and 80 percent of other neonatal and pediatric stays are selected from each hospital that is sampled for patients younger than 21 years of age.

The KID contains clinical and resource use information included in a typical discharge abstract, with safeguards to protect the privacy of individual patients, physicians, and hospitals (as required by data sources). It includes discharge status, diagnoses, procedures, patient demographics (e.g., sex, age), expected source of primary payment (e.g., Medicare, Medicaid, private insurance, self-pay, and other insurance types), and hospital charges and cost.

Restricted access data files are available with a data use agreement and brief online security training.

The Healthcare Cost and Utilization Project (HCUP) Nationwide Emergency Department Sample (NEDS) is the largest all-payer emergency department (ED) database in the United States. yielding national estimates of hospital-owned ED visits. Unweighted, it contains data from over 30 million ED visits each year. Weighted, it estimates roughly 145 million ED visits nationally. Developed through a Federal-State-Industry partnership sponsored by the Agency for Healthcare Research and Quality, HCUP data inform decision making at the national, State, and community levels.

Sampled from the HCUP State Inpatient Databases (SID) and State Emergency Department Databases (SEDD), the HCUP NEDS can be used to create national and regional estimates of ED care. The SID contain information on patients initially seen in the ED and subsequently admitted to the same hospital. The SEDD capture information on ED visits that do not result in an admission (i.e., treat-and-release visits and transfers to another hospital). Developed through a Federal-State-Industry partnership sponsored by the Agency for Healthcare Research and Quality, HCUP data inform decision making at the national, State, and community levels.

The NEDS contain information about geographic characteristics, hospital characteristics, patient characteristics, and the nature of visits (e.g., common reasons for ED visits, including injuries). The NEDS contains clinical and resource use information included in a typical discharge abstract, with safeguards to protect the privacy of individual patients, physicians, and hospitals (as required by data sources). It includes ED charge information for over 85% of patients, regardless of expected payer, including but not limited to Medicare, Medicaid, private insurance, self-pay, or those billed as ‘no charge’. The NEDS excludes data elements that could directly or indirectly identify individuals, hospitals, or states.Restricted access data files are available with a data use agreement and brief online security training.