The National Health and Nutrition Examination Survey (NHANES) is a program of studies designed to assess the health and nutritional status of adults and children in the United States. An ongoing annual survey combines interviews and physical examinations. The NHANES interview includes demographic, socioeconomic, dietary, and health-related questions. The examination component consists of medical, dental, and physiological measurements, as well as laboratory tests administered by highly trained medical personnel.
Ancillary studies include the NHANES National Youth Fitness Survey (NNYFS) and NHANES Epidemiologic Followup Study (NHEFS). NNYFS was conducted in 2012 to evaluate the physical activity and fitness of children aged 3 to 15 years old through interviews and fitness tests. NHEFS is a longitudinal survey of adults aged 25 to 74 years old in the NHANES I (1971-1975) cohort who completed a medical examination. Data was collected in follow-up rounds in 1982-1984, 1986, 1987, and 1992 through subject and proxy interviews and vital record search. Available data files include vital and tracing status, demographic information, interview data on health status, health care facility inpatient data, and mortality data.
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analyze the national health and nutrition examination survey (nhanes) with r nhanes is this fascinating survey where doctors and dentists accompany survey interviewers in a little mobile medical center that drives around the country. while the survey folks are interviewing people, the medical professionals administer laboratory tests and conduct a real doctor's examination. the b lood work and medical exam allow researchers like you and me to answer tough questions like, "how many people have diabetes but don't know they have diabetes?" conducting the lab tests and the physical isn't cheap, so a new nhanes data set becomes available once every two years and only includes about twelve thousand respondents. since the number of respondents is so small, analysts often pool multiple years of data together. the replication scripts below give a few different examples of how multiple years of data can be pooled with r. the survey gets conducted by the centers for disease control and prevention (cdc), and generalizes to the united states non-institutional, non-active duty military population. most of the data tables produced by the cdc include only a small number of variables, so importation with the foreign package's read.xport function is pretty straightforward. but that makes merging the appropriate data sets trickier, since it might not be clear what to pull for which variables. for every analysis, start with the table with 'demo' in the name -- this file includes basic demographics, weighting, and complex sample survey design variables. since it's quick to download the files directly from the cdc's ftp site, there's no massive ftp download automation script. this new github repository co ntains five scripts: 2009-2010 interview only - download and analyze.R download, import, save the demographics and health insurance files onto your local computer load both files, limit them to the variables needed for the analysis, merge them together perform a few example variable recodes create the complex sample survey object, using the interview weights run a series of pretty generic analyses on the health insurance ques tions 2009-2010 interview plus laboratory - download and analyze.R download, import, save the demographics and cholesterol files onto your local computer load both files, limit them to the variables needed for the analysis, merge them together perform a few example variable recodes create the complex sample survey object, using the mobile examination component (mec) weights perform a direct-method age-adjustment and matc h figure 1 of this cdc cholesterol brief replicate 2005-2008 pooled cdc oral examination figure.R download, import, save, pool, recode, create a survey object, run some basic analyses replicate figure 3 from this cdc oral health databrief - the whole barplot replicate cdc publications.R download, import, save, pool, merge, and recode the demographics file plus cholesterol laboratory, blood pressure questionnaire, and blood pressure laboratory files match the cdc's example sas and sudaan syntax file's output for descriptive means match the cdc's example sas and sudaan synta x file's output for descriptive proportions match the cdc's example sas and sudaan syntax file's output for descriptive percentiles replicate human exposure to chemicals report.R (user-contributed) download, import, save, pool, merge, and recode the demographics file plus urinary bisphenol a (bpa) laboratory files log-transform some of the columns to calculate the geometric means and quantiles match the 2007-2008 statistics shown on pdf page 21 of the cdc's fourth edition of the report click here to view these five scripts for more detail about the national health and nutrition examination survey (nhanes), visit: the cdc's nhanes homepage the national cancer institute's page of nhanes web tutorials notes: nhanes includes interview-only weights and interview + mobile examination component (mec) weights. if you o nly use questions from the basic interview in your analysis, use the interview-only weights (the sample size is a bit larger). i haven't really figured out a use for the interview-only weights -- nhanes draws most of its power from the combination of the interview and the mobile examination component variables. if you're only using variables from the interview, see if you can use a data set with a larger sample size like the current population (cps), national health interview survey (nhis), or medical expenditure panel survey (meps) instead. confidential to sas, spss, stata, sudaan users: why are you still riding around on a donkey after we've invented the internal combustion engine? time to transition to r. :D
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The National Health and Nutrition Examination Surveys (NHANES) is a program of studies designed to assess the health and nutritional status of adults and children in the United States. The NHANES combines personal interviews and physical examinations, which focus on different population groups or health topics. These surveys have been conducted by the National Center for Health Statistics (NCHS) on a periodic basis from 1971 to 1994. In 1999 the NHANES became a continuous program with a changing focus on a variety of health and nutrition measurements which were designed to meet current and emerging concerns. The surveys examine a nationally representative sample of approximately 5,000 persons each year. These persons are located in counties across the United States, 15 of which are visited each year. The 2001-2002 NHANES contains data for 11,039 individuals (and MEC examined sample size of 10,477) of all ages. Many questions that were asked in NHANES II, 1976-1980, Hispanic HANES 1982-1984, and NHANES III, 1988-1994, were combined with new questions in the NHANES 2001-2002. As in past health examination surveys, data were collected on the prevalence of chronic conditions in the population. Estimates for previously undiagnosed conditions, as well as those known to and reported by survey respondents, are produced through the survey. Risk factors, those aspects of a person's lifestyle, constitution, heredity, or environment that may increase the chances of developing a certain disease or condition, were examined. Data on smoking, alcohol consumption, sexual practices, drug use, physical fitness and activity, weight, and dietary intake were collected. Information on certain aspects of reproductive health, such as use of oral contraceptives and breastfeeding practices, were also collected. The diseases, medical conditions, and health indicators that were studied include: anemia, cardiovascular disease, diabetes and lower extremity disease, environmental exposures, equilibrium, hearing loss, infectious diseases and immunization, kidney disease, mental health and cognitive functioning, nutrition, obesity, oral health, osteoporosis, physical fitness and physical functioning, reproductive history and sexual behavior, respiratory disease (asthma, chronic bronchitis, emphysema), sexually transmitted diseases, skin diseases, and vision. The sample for the survey was selected to represent the United States population of all ages. Special emphasis in the 2001-2002 NHANES was on adolescent health and the health of older Americans. To produce reliable statistics for these groups, adolescents aged 15-19 years and persons aged 60 years and older were over-sampled for the survey. African Americans and Mexican Americans were also over-sampled to enable accurate estimates for these groups. Several important areas in adolescent health, including nutrition and fitness and other aspects of growth and development, were addressed. Since the United States has experienced dramatic growth in the number of older people during the twentieth century, the aging population has major implications for health care needs, public policy, and research priorities. NCHS is working with public health agencies to increase the knowledge of the health status of older Americans. NHANES has a primary role in this endeavor. In the examination, all participants visit the physician who takes their pulse or blood pressure. Dietary interviews and body measurements are included for everyone. All but the very young have a blood sample taken and see the dentist. Depending upon the age of the participant, the rest of the examination includes tests and procedures to assess the various aspects of health listed above. Usually, the older the individual, the more extensive the examination. Some persons who are unable to come to the examination center may be given a less extensive examination in their homes. Demographic data file variables are grouped into three broad categories: (1) Status Variables: provide core information on the survey participant. Examples of the core variables include interview status, examination status, and sequence number. (Sequence number is a unique ID assigned to each sample person and is required to match the information on this demographic file to the rest of the NHANES 2001-2002 data). (2) Recoded Demographic Variables: these variables include age (
1999-2008; 2005-2008. This dataset is a de-identified summary table of vision and eye health data indicators from NHANES, stratified by all available combinations of age group, race/ethnicity, gender, and risk factor. NHANES is a program of studies conducted by the National Center for Health Statistics at CDC designed to assess the health and nutritional status of adults and children in the U.S, and combines interviews and physical examinations. NHANES stopped collecting vision and eye health data in 2008. Approximate sample size is 5,000 persons per year. NHANES data for VEHSS includes questions and examinations related to Visual Function, Vision Exam Measures, Eye Health Conditions, Service Utilization, and Examination Measures. Data were suppressed for cell sizes less than 30 persons, or where the relative standard error more than 30% of the mean. Detailed information on VEHSS NHANES analyses can be found on the VEHSS NHANES webpage (https://www.cdc.gov/visionhealth/vehss/data/national-surveys/national-health-and-nutrition-examination-survey.html). Additional information about NHANES can be found on the NHANES website (https://www.cdc.gov/nchs/nhanes/index.htm). The VEHSS NHANES dataset was last updated in June 2018.
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This data tape contains demographic data and behavior questionnaire data for persons 25 through 74 years of age examined in the second National Health and Nutrition Examination Survey (NHANES II), conducted in 1976-1980 by the National Center for Health Statistics, U.S. Public Health Service.
https://www.icpsr.umich.edu/web/ICPSR/studies/9854/termshttps://www.icpsr.umich.edu/web/ICPSR/studies/9854/terms
The National Health and Nutrition Examination Survey I Epidemiologic Follow-Up Study (NHEFS) is a longitudinal study which uses as its baseline those adult persons aged 25 to 74 years who were examined in the first National Health and Nutrition Examination Survey (NHANES I). The NHEFS surveys were designed to investigate the association between factors measured at the baseline and the development of specific health conditions. The NHEFS is comprised of a series of follow-up surveys, three of which have been completed. The first wave of data collection, the 1982-1984 NHEFS (ICPSR 8900), included all persons who were between 25 and 74 years of age at their NHANES I examination. The second wave of data collection, the 1986 NHEFS (ICPSR 9466), included the NHEFS cohort who were 55-74 years at their baseline examination and not known to be deceased at the time of the 1982-1984 NHEFS. The third wave, the 1987 NHEFS, was conducted for the entire nondeceased NHEFS cohort. The 1982-1984 NHEFS consisted of five steps. The first step focused on tracing and locating all subjects in the cohort or their proxies and determining their vital status. The second step involved obtaining death certificates for subjects who were deceased. Interviews with the participants or their proxies constituted the third phase of the follow-up. The fourth phase of the follow-up included measurements of pulse, blood pressure, and weight for interviewed respondents, and the fifth step was the acquisition of relevant hospital and nursing home records, including pathology reports and electrocardiograms. The 1986 NHEFS assessed changes to the health and functional status of the oldest members of the NHEFS cohort since the last contact period. The 1987 NHEFS also collected information on changes in the health and functional status of the NHEFS cohort since the last contact period. The Vital and Tracing Status file contains summary information about the status of the entire NHEFS cohort. The Health Care Facility Record file contains information on reports of stays in hospitals and nursing homes as well as information abstracted from facility medical records. The Mortality Data file contains data abstracted from the death certificates from all three NHEFS surveys. The Interview Data file contains information on selected aspects of the subject's health history since the time of the NHANES I exam.
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:
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Analysis of ‘National Health and Nutrition Examination Survey (NHANES) – Vision and Eye Health Surveillance’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/17db5667-8dc2-48f5-aba9-e42cbb10a1f2 on 12 February 2022.
--- Dataset description provided by original source is as follows ---
1999-2008; 2005-2008. This dataset is a de-identified summary table of vision and eye health data indicators from NHANES, stratified by all available combinations of age group, race/ethnicity, gender, and risk factor. NHANES is a program of studies conducted by the National Center for Health Statistics at CDC designed to assess the health and nutritional status of adults and children in the U.S, and combines interviews and physical examinations. NHANES stopped collecting vision and eye health data in 2008. Approximate sample size is 5,000 persons per year. NHANES data for VEHSS includes questions and examinations related to Visual Function, Vision Exam Measures, Eye Health Conditions, Service Utilization, and Examination Measures. Data were suppressed for cell sizes less than 30 persons, or where the relative standard error more than 30% of the mean. Detailed information on VEHSS NHANES analyses can be found on the VEHSS NHANES webpage (https://www.cdc.gov/visionhealth/vehss/data/national-surveys/national-health-and-nutrition-examination-survey.html). Additional information about NHANES can be found on the NHANES website (https://www.cdc.gov/nchs/nhanes/index.htm). The VEHSS NHANES dataset was last updated in June 2018.
--- Original source retains full ownership of the source dataset ---
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Liver steatosis scores (CAP Score) were investigated using data from the National Center for Health Statistics examination survey (NHANES) for 2017-2018 and 2017-March 2020. The datasets include demographics, dietary, examination, laboratory, and questionnaire databases. Each dataset consists of a set of SAS files converted to CSV files using the SAS Viewer software. The selected variables for this analysis are systolic and diastolic blood pressure, total cholesterol, insulin, triglycerides, elasticity score, and CAP scores. Before data cleaning, the total number of records was 8,056 with ten columns. However, after data cleaning, the remaining records used in the analysis were 6,394, with only six columns.
This data package contains the National Health Surveys. The NHIS is one of the major programs of data collection of the Nation Center for Health Satistics of the Centers for Disease Control and Prevention, is a recopilation of information on the amount, distribution and effects of diseases and disability in the US.
The dataset, Survey-SR, provides the nutrient data for assessing dietary intakes from the national survey What We Eat In America, National Health and Nutrition Examination Survey (WWEIA, NHANES). Historically, USDA databases have been used for national nutrition monitoring (1). Currently, the Food and Nutrient Database for Dietary Studies (FNDDS) (2), is used by Food Surveys Research Group, ARS, to process dietary intake data from WWEIA, NHANES. Nutrient values for FNDDS are based on Survey-SR. Survey-SR was referred to as the "Primary Data Set" in older publications. Early versions of the dataset were composed mainly of commodity-type items such as wheat flour, sugar, milk, etc. However, with increased consumption of commercial processed and restaurant foods and changes in how national nutrition monitoring data are used (1), many commercial processed and restaurant items have been added to Survey-SR. The current version, Survey-SR 2013-2014, is mainly based on the USDA National Nutrient Database for Standard Reference (SR) 28 (2) and contains sixty-six nutrientseach for 3,404 foods. These nutrient data will be used for assessing intake data from WWEIA, NHANES 2013-2014. Nutrient profiles were added for 265 new foods and updated for about 500 foods from the version used for the previous survey (WWEIA, NHANES 2011-12). New foods added include mainly commercially processed foods such as several gluten-free products, milk substitutes, sauces and condiments such as sriracha, pesto and wasabi, Greek yogurt, breakfast cereals, low-sodium meat products, whole grain pastas and baked products, and several beverages including bottled tea and coffee, coconut water, malt beverages, hard cider, fruit-flavored drinks, fortified fruit juices and fruit and/or vegetable smoothies. Several school lunch pizzas and chicken products, fast-food sandwiches, and new beef cuts were also added, as they are now reported more frequently by survey respondents. Nutrient profiles were updated for several commonly consumed foods such as cheddar, mozzarella and American cheese, ground beef, butter, and catsup. The changes in nutrient values may be due to reformulations in products, changes in the market shares of brands, or more accurate data. Examples of more accurate data include analytical data, market share data, and data from a nationally representative sample. Resources in this dataset:Resource Title: USDA National Nutrient Database for Standard Reference Dataset for What We Eat In America, NHANES 2013-14 (Survey SR 2013-14). File Name: SurveySR_2013_14 (1).zipResource Description: Access database downloaded on November 16, 2017. US Department of Agriculture, Agricultural Research Service, Nutrient Data Laboratory. USDA National Nutrient Database for Standard Reference Dataset for What We Eat In America, NHANES (Survey-SR), October 2015. Resource Title: Data Dictionary. File Name: SurveySR_DD.pdf
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.
This data represents the age-adjusted prevalence of high total cholesterol, hypertension, and obesity among US adults aged 20 and over between 1999-2000 to 2017-2018. Notes: All estimates are age adjusted by the direct method to the U.S. Census 2000 population using age groups 20–39, 40–59, and 60 and over. Definitions Hypertension: Systolic blood pressure greater than or equal to 130 mmHg or diastolic blood pressure greater than or equal to 80 mmHg, or currently taking medication to lower high blood pressure High total cholesterol: Serum total cholesterol greater than or equal to 240 mg/dL. Obesity: Body mass index (BMI, weight in kilograms divided by height in meters squared) greater than or equal to 30. Data Source and Methods Data from the National Health and Nutrition Examination Surveys (NHANES) for the years 1999–2000, 2001–2002, 2003–2004, 2005–2006, 2007–2008, 2009–2010, 2011–2012, 2013–2014, 2015–2016, and 2017–2018 were used for these analyses. NHANES is a cross-sectional survey designed to monitor the health and nutritional status of the civilian noninstitutionalized U.S. population. The survey consists of interviews conducted in participants’ homes and standardized physical examinations, including a blood draw, conducted in mobile examination centers.
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Characteristics in study sample (N = 26,382).
https://www.icpsr.umich.edu/web/ICPSR/studies/8900/termshttps://www.icpsr.umich.edu/web/ICPSR/studies/8900/terms
The National Health and Nutrition Examination Survey I Epidemiologic Followup Study (NHEFS) originated as a joint project between the National Center for Health Statistics (NCHS) and the National Institute on Aging (NIA). The design of NHEFS, which contains follow-up data on the NHANES I cohort, consisted of five steps. The first step focused on tracing and locating all subjects in the cohort or their proxies and determining their vital status. The second step involved the obtaining of death certificates for subjects who were deceased. Interviews with the participants or their proxies constituted the third phase of the follow-up. The fourth phase of the follow-up included measurements of pulse, blood pressure, and weight for interviewed respondents, and the fifth step was the acquisition of relevant hospital and nursing home records, including pathology reports and electrocardiograms. The respondent interview was designed to gather information on selected aspects of the subject's health history since the time of the NHANES I exam. This information included a history of the occurrence or recurrence of selected medical conditions, an assessment of behavioral, social, nutritional, and medical risk factors believed to be associated with these conditions, and an assessment of various aspects of functional status. Whenever possible, the questionnaire was designed to retain item comparability between NHANES I and NHEFS in order to measure change over time. However, questionnaire items were modified, added, or deleted when necessary to take advantage of recent improvements in questionnaire methodology. The Vital and Tracing Status file is a master file containing tracing, vital status, and demographic data for all NHEFS respondents. In addition, it provides users with information on the availability of different survey components for each respondent. For example, variables have been created to indicate whether a death certificate was received for a deceased subject, hospital records were received, or a follow-up interview was completed. The Health Care Facility Record file offers data on respondents who had reported an overnight stay in a health care facility after 1970. Information on the name and address of the facility, the date of the stay, and the reason for the stay was recorded. The Mortality Data file contains death certificate information for 1,935 NHEFS decedents. The death certificate information is for deaths occurring from 1971 to 1983.
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Distribution of assets in study sample of U.S. adults by race/ethnicity (N = 26,382).
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Baseline characteristics of US adults by NHANES surveys.
The 17,000 NHANES images are available in the following formats:
jpg - full spatial resolution and 8-bit grayscale jpgahe – jpg with adaptive histogram equalization (AHE) jpgaheus - jpg with adaptive histogram equalization (AHE) followed by unsharp masking tif8 - full spatial resolution and 8-bit grayscale resolution in TIFF format tif8roi - A small subset of the cervical spine images is available at full spatial resolution and 8-bit, cropped to regions of interest containing the spine area fullres - The 17,000 NHANES II images at full spatial and full 12-bit grayscale resolution, in raw "nh2" format, uncompressed marks - Vertebra coordinate values for a subset of about 600 of the images is available in ASCII text format
Information about the Second National Health and Nutrition Examination Survey (NHANES II)
The National Health and Nutrition Examination Surveys
The National Health and Nutrition Examination Surveys (NHANES), conducted by the National Center for Health Statistics, Centers for Disease Control (NCHS/CDC), were designed to assess the health and nutritional status of adults and children in the United States through interviews and direct physical examinations.
These images are the digitized versions of the 17,000 x-ray films collected during the Second National Health and Nutrition Examination Survey (NHANES II) conducted by the NCHS during the years 1976-1980. In NHANES II 20,322 individuals were both interviewed and examined. For examined persons aged 25 through 74, two x-rays were made, with the exceptions that no x-rays were taken of pregnant women and no lumbar x-rays were taken on women under 50 years of age. X-rays of the cervical and lumbar spines were taken to provide evidence of osteoarthitis and degenerative disc disease.
The films were subsequently digitized at a horizontal and vertical sampling rate of 146 dpi using Lumisys laser scanning equipment.
The NHANES radiographs were scanned by Dr. Bernie Huang at the University of California at Los Angeles and the University of California at San Francisco. Dr. Huang’s group used a Lumysis 100 with a 175 micron spot to scan the first 6000 radiographs. The remaining radiographs were scanned on the Lumysis 150 again with a 175 micron spot size.
NOTE: This dataset is no-longer updated with new content.
https://search.gesis.org/research_data/datasearch-httpwww-da-ra-deoaip--oaioai-da-ra-de443344https://search.gesis.org/research_data/datasearch-httpwww-da-ra-deoaip--oaioai-da-ra-de443344
Abstract (en): Information for all examined sampled persons in each of these National Health and Nutrition Examination Surveys (NHANES I) was obtained by means of a household interview, a general medical history, a 24-hour dietary intake recall interview, a food frequency interview, a food program questionnaire, a general medical examination, dental, dermatological and ophthalmological examinations, anthropometric measurement, hand-wrist x-rays (of persons ages 1-17 only) and 24 hematological, blood chemistry, and urological laboratory determinations. In addition to this information, some respondents were given more specific tests such as x-rays of the chest and hip and knee joints, audiometry, electrocariography, goniometry, spirometry, pulmonary diffusion and tuberculin tests, and additional laboratory determinations. This data set contains demographic characteristics for 6913 examinees ages 25-74 who had received the detailed examination during NHANES I. Additional information includes their lung and heart size measurements, three expert x-ray readings for lung and heart pathology, pulmonary diffusion measurements, and tuberculin test results. The civilian noninstitutionalized population, ages 1-74, of the United States at the midpoint of the survey (November 1, 1972). NHANES I is a multistage stratified probability sample of clusters of persons in landbased segments. The subsample of 6913 adults to receive this detailed health examination was chosen systematically from the nutrition sample after a random start. An age-specific sampling rate was used.
The National Health and Nutrition Examination Survey (NHANES) is a program of studies designed to assess the health and nutritional status of adults and children in the United States. An ongoing annual survey combines interviews and physical examinations. The NHANES interview includes demographic, socioeconomic, dietary, and health-related questions. The examination component consists of medical, dental, and physiological measurements, as well as laboratory tests administered by highly trained medical personnel.
Ancillary studies include the NHANES National Youth Fitness Survey (NNYFS) and NHANES Epidemiologic Followup Study (NHEFS). NNYFS was conducted in 2012 to evaluate the physical activity and fitness of children aged 3 to 15 years old through interviews and fitness tests. NHEFS is a longitudinal survey of adults aged 25 to 74 years old in the NHANES I (1971-1975) cohort who completed a medical examination. Data was collected in follow-up rounds in 1982-1984, 1986, 1987, and 1992 through subject and proxy interviews and vital record search. Available data files include vital and tracing status, demographic information, interview data on health status, health care facility inpatient data, and mortality data.