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First National Health and Nutrition Examination Survey (NHANES I) Public-use Data Files

Survey description
Data file description
List of data file variables
Technical characteristics
Geographic coverage
Data availability
Ordering information
Documentation contents
Related reports
Contacts
NHANES Web Site

Survey description
The First National Health and Nutrition Examination Survey (NHANES I) was conducted on a nationwide probability sample of approximately 32,000 persons 1-74 years of age. The NHANES I sample was selected so that certain population groups thought to be at high risk of malnutrition (persons with low incomes, preschool children, women of childbearing age, and the elderly) were oversampled at preset rates. On completion of the survey, 31,973 sample persons had been interviewed; of these, 23,808 people were examined. Adjusted sampling weights were computed within 60 age-sex-race categories in order to inflate the sample so as to closely reflect the U.S. civilian noninstitutionalized population 1-74 years of age at the midpoint of the survey.

Although a major emphasis of NHANES I was on nutrition and some limited aspects of health, a subset of 3,854 persons 25-74 years of age received a more detailed health examination. No oversampling of subgroups of the population was done in this subsample, as it had been for the major nutrition component. This subsample is representative of the U.S. population 25-74 years of age at the midpoint of NHANES I. After the nutrition survey was completed, the detailed medical examination was given to adults 25-74 years of age. This portion of the survey is referred to as the NHANES I Augmentation and was continued through October 1975, bringing the total number of persons who received a detailed examination to 6,913.

List of data file variables at a glance
Anthropometry, goniometry, skeletal age, bone density, and cortical thickness, ages 1-74 years (Tape no. 4111)
Demographic characteristics, height, weight, and a series of body and skinfold measurements. Skeletal maturation data from x rays of hand and wrist for persons aged 1-17 years. Goniometry, cortical thickness, and bone density data for persons aged 25-74 years. Data were gathered for 23,808 sample persons aged 1-74 years who were examined during NHANES I and the NHANES I Augmentation.
Arthritis, ages 25-74 years (Tape no. 4121)
Demographic characteristics. Information from an arthritis history supplement including history of arthritis; pain or aching in joints, neck, back, or hip with joint swelling and stiffness; and assessments from x-ray films of hip-sacroiliac and knee. Data were gathered for sample persons who received the detailed health examination during NHANES I and the NHANES I Augmentation.
Audiometric test, ages 25-74 years (Tape no. 4241)
Demographic characteristics. Results of three audiometric tests: air condition, bone condition, and speech reception. Pure-tone audiometric test data for sample persons who received the detailed medical examination, 3,854 adults who received a bone-conduction test during NHANES I, and 3,059 adults who received a speech reception test during the NHANES I Augmentation.
Biochemistry, serology, hematology, peripheral blood slide, and urinary findings, ages 1-74 years (Tape no. 4800)
Demographic characteristics. Results of 24 hematological, blood chemistry, serological, and urine laboratory tests. Responses to questions relevant to the interpretation of the tests.
Computer measurements and interpretations of electrocardiograms, ages 25-74 years (Tape no. 4140)
Demographic characteristics. Computer measurements and interpretations of electrocardiograms. Data were gathered for persons who received the detailed medical examination during NHANES I and the NHANES I Augmentation.
Dental, ages 1-74 years (Tape no. 4235)
Demographic characteristics. Results of a standardized dental examination by staff dentists focusing on dental health status, treatment needs, and occlusion. Derived indexes of dental health are also included.
Dermatology, ages 1-74 years (Tape no. 4151)
Demographic characteristics. Results of a complete clinical examination of the skin and subcutaneous tissue that considered normal variations in texture, certain manifestations of aging, and all pathologic changes; results of tissue biopsies, Tzanck smears, and cultures documenting significant diagnoses; estimates of light exposure experienced and actinic damage; occupational contactants and allergens; judgments of discomfort and disability from hand, foot, or generalized skin problems; and information concerning care sought and adequacy of care received.
Dietary frequency and adequacy, ages 1-74 years (Tape no. 4701)
Demographic characteristics. Food frequency data and total nutrient intake from the 24-hour recall dietary interview. This total nutrient intake is then expressed as a percent of the dietary standards employed in NHANES I in an attempt to assess dietary adequacy.
Dietary frequency and adequacy, ages 1-74 years (Tape no. 4701)
Demographic characteristics. Food frequency data and total nutrient intake from the 24-hour recall dietary interview. This total nutrient intake is then expressed as a percent of the dietary standards employed in NHANES I in an attempt to assess dietary adequacy.
General well-being and the CES-D depression scale developed by the National Institute of Mental Health, ages 25-74 years (Tape no. 4171)
Demographic characteristics. General well-being schedule and CES-D (Center for Epidemiologic Studies Depression Scale), including responses to questions about feeling of well-being (during the month prior to examination), depression, and past psychiatric care. Data were gathered for sample persons who received the detailed medical examination during NHANES I and the NHANES I Augmentation.
Health care needs, general medical history, sample person supplement, and respiratory and cardiovascular supplements, ages 25-74 years (Tape no. 4091)
Demographic characteristics. Information from five questionnaires: (1) Health Care Needs, (2) General Medical History, (3) Sample Person Supplement, (4) Cardiovascular Supplement, and (5) Respiratory Supplement. Responses to questions about hearing; vision; hypertension; dental, diabetic, arthritic, respiratory, and cardiovascular conditions; and frequency, nature, insurance, and payment for health care. Data were gathered for 6,913 sample persons aged 25-74 years who received the detailed medical examination during NHANES I and the NHANES I Augmentation.
Medical examination, ages 1-74 years (Tape no. 4233)
Demographic characteristics. Results of a standardized medical examination given by the survey staff physicians that focused primarily on clinical signs of nutritional deficiencies. Also includes findings from the subsample of adults ages 25-74 years who were given a more detailed examination with an emphasis on cardiovascular, respiratory, and musculoskeletal systems; and the ear, nose, and throat.
Medical history questionnaire, ages 1-11 years (Tape no. 4067)
Demographic characteristics. Information from infant and child medical histories, including responses to questions about breast feeding, immunizations, early development, and various medical conditions on 4,972 children aged 1-11 years who were examined during NHANES I.
Medical history questionnaire, ages 1-11 years (Tape no. 4067)
Demographic characteristics. Information from infant and child medical histories, including responses to questions about breast feeding, immunizations, early development, and various medical conditions on 4,972 children aged 1-11 years who were examined during NHANES I.
Model gram and nutrient composition (Tape nos. 4702 and 4703)
Model gram tape--3,500 food items with food groups; food codes; alphanumeric descriptions; preferred food model codes; and gram conversion factors. Nutrient composition tape--the actual nutrient analysis in 100-gram edible portions of all foods listed in the model gram tape. These tapes are essentially an interpretive tool for use as input to a computer analysis of NHANES I 24-hour recall. Gram conversion factors and nutrient composition information for approximately 3,500 foods used in dietary intake analysis of NHANES I data.
Near and distant vision, ages 25-74 years (Tape no. 4163)
Demographic characteristics. Results from a near-and-distance vision screening examination. Data were gathered for sample persons examined from July 1974 to October 1975 during the NHANES I Augmentation.
Ophthalmology, ages 1-74 years (Tape no. 4161)
Demographic characteristics. Ocular histories, including previously known eye disorders or previous eye surgery. Standardized eye examination with certain components of the examination given to people of different ages. Data were gathered on a subsample of 10,127 sample persons examined at the first 35 locations of NHANES I.
Pulmonary diffusion, TB, chest x-ray planimetry, heart size, and lung and heart pathology, ages 25-74 years (Tape no. 4251)
Demographic characteristics. Results of single-breath carbon monoxide diffusion studies, tuberculin skin tests, and readings of chest x-rays for each sample person.
Spirometry best trials only, ages 25-74 years (Tape no. 4250)
Demographic characteristics. Results of a five or more trial set Forded Expiratory Spirogram. This test provided measures of respiratory performance and capacity.
24-hour food consumption intake, ages 1-74 years (Tape no. 4704)
Demographic characteristics. Information on specific food items and quantities ingested for all regular meals and between-meal foods or snacks consumed on the day (midnight to midnight) preceding the interview for each sample person. Because of the survey design, the recall period did not generally include Saturday or Sunday. Data were collected for 20,749 sample persons.

Data file technical characteristics
All files are fixed length, blocked files. Other data tape characteristics are listed below:

Geographic coverage
The NHANES I included the civilian noninstitutionalized population of the conterminous United States.

Data availability
Data from both the main nutrition component and the augmentation portion of NHANES I are available for 1971-75. The survey started in April 1971; the nutrition component and some general health components were completed in June 1974. Data from this study are only available on tape. Updated radiographic absorptiometry bone density data are avalable on diskette.

Additionally, a followup of NHANES I participants has been conducted. Other studies similar to the NHANES I are: HHANES, NHANES II, NHANES III and NHES, Cycle 1, Cycle 2, and
Cycle 3.

Ordering information
Data tapes from the HHANES can only be purchased through the National Technical Information Service (NTIS). The NTIS order numbers are as follows:

Documentation contents
Data tape documentation packages contain a brief description of NHANES I, general notes on the specific subject matter of the tape, and brief statements about the use of NHANES I data, including discussion of possible sources of error and variance estimation procedures. Sampling weights are included in the demographic section of the data tapes. Detailed notes explain certain items that are not self-explanatory or not documented elsewhere.

Related reports
A detailed description of the design and operation of NHANES I is provided in Vital and Health Statistics Series 1, Nos. 10a, 10b, and 14, in which the contents of NHANES I are described in detail and the rationale and purpose for the inclusion of various components of the examination are discussed. A few reports that contain results from NHANES I are available in Vital and Health Statistics, Series 11, and in selected Advance Data reports

This page last reviewed September 04, 2008