National Health and Nutrition Examination Survey

Rohit Khare (
Sun, 10 Aug 1997 02:56:50 -0400

[RK: My mom works as a lead statistician and survey designer on this project:
NHANES goes around the country in a set of semitrailers doing full physical
workups on US population samples. It's the definitive profile of American
health (e.g. things like Height/Weight charts, AIDS seroprevalence (also my
mom's focus))]

For the record, my dad runs Envirosystems:
(an embarassingly sparse site I have yet to work seriously on -- and I
don't know WHO put all those animations in)]

Updated 11/08/96

National Health and Nutrition Examination Survey

The National Center for Health Statistics (NCHS) has conducted seven health
examination surveys of the U.S. population since 1960, including the
recently completed Third National Health and Nutrition Examination Survey
(NHANES III). The surveys were designed to obtain nationally representative
information on the health and nutritional status of the population of the
United States through interviews and direct physical examinations. Physical
examinations and objective measures are employed because the information
collected cannot be furnished or is not available in a standardized manner
through interviews with the people themselves or through records maintained
by the health professionals who provide their medical care.

The goals of the NHANES program are:

To estimate the number and percent of persons in the U.S. population and
designated subgroups with selected diseases and risk factors, for selected
diseases, to study the relationship between diet, nutrition and health, and
to explore emerging public health issues.

The eligible population for the NHANES III was the U.S. civilian
noninstitutionalized population aged 2 months or older. The sample design
employed a stratified multistage probability sample of counties, blocks,
and persons randomly selected from households. The periods 1988-91 and
1991-94 each constituted national samples of the U.S. population.
Eighty-one counties were selected from 26 States from which approximately
40,000 persons of all races were selected and about 30,000 agreed to
participate in the medical examination. Precise estimates of health
characteristics were needed for relatively small subsets of the population
(children, older persons, Black Americans, and Mexican Americans) and these
groups were selected in greater numbers than would have occurred without
over sampling.

Some of the 30 topics investigated in the NHANES III were: high blood
pressure, high blood cholesterol, obesity, passive smoking, lung disease,
osteoporosis, HIV, hepatitis, helicobacter pylori, immunization status,
diabetes, allergies, growth and development, blood lead, anemia, food
sufficiency, dietary intake including fats, antioxidants and nutritional
blood measures.

The Hispanic Health and Nutrition Examination Survey, a one-time survey
conducted from 1982-84, provides data on a 12,000-person sample of the
three major subgroups of the Hispanic population--Mexican Americans in the
Southwest; Cubans in Miami (Dade County), Florida; and Puerto Ricans in the
New York City area.

Descriptions of the HANES programs appear in the NCHS Vital and Health
Statistics series 1; and methodological reports appear in series 2. The
summary survey findings are published in NCHS Vital and Health Statistics
series 11, Advance Data From Vital and Health Statistics, and Centers for
Disease Control and Prevention's Morbidity and Mortality Weekly Report. The
specific topics are published in a broad variety of professional journals.
Public-use data files from these studies are available on data tape.

NHANES I Epidemiologic Followup Study

The NHANES I Epidemiologic Followup Study (NHEFS) is a national
longitudinal study designed to investigate the relationships between
clinical, nutritional, and behavioral factors assessed at baseline NHANES
I, and subsequent morbidity, mortality, and institutionalization. The NHEFS
population includes the 14,407 participants who were 25-74 years of age
when first examined in NHANES I (1971-75). NHEFS is a collaborative project
involving the NCHS, the National Institute on Aging, other components of
the National Institutes of Health, the Substance Abuse and Mental Health
Services Administration, and other Centers in CDC.
NHEFS provides data on mortality, morbidity, and hospital utilization as
well as changes in risk factors, functional limitation, and
institutionalization between NHANES I and the followup recontacts.

The first wave (1982-84) of data collection was conducted for all members
of the NHEFS cohort. It included tracing the cohort; conducting personal
interviews with subjects or their proxies; measuring pulse rate, weight,
and blood pressure of surviving participants; collecting hospital and
nursing home records of overnight stays; and collecting death certificates
of decedents.

The continued followups of the NHEFS population were conducted in 1986,
1987, and 1992 using the same design and data collection procedures
developed in the 1982-84 NHEFS, with the exception that a 30-minute
computer-assisted telephone interview was administered rather than a
personal interview, and no physical measurements were taken. The 1986 NHEFS
was conducted on members of the cohort who were 55-74 years of age at their
baseline examination and not known to be deceased. The 1987 and 1992 NHEFS
was conducted on the entire nondeceased NHEFS cohort.

NHEFS public-use data tapes and documentation are available from the
National Technical Information Service. A set of four data tapes containing
information on vital and tracing status, subject and proxy interviews,
health care facility stays in hospitals and nursing homes, and mortality
data from death certificates is available for each NHEFS followup wave. All
NHEFS public-use data tapes can be linked to the NHANES I public-use data
tapes. Descriptions of the NHEFS study methodologies and survey instruments
are available in the NCHS Vital and Health Statistics series 1, and
statistical issues in analyzing NHEFS data are addressed in series 2.

Rohit Khare /// MCI Internet Architecture (BOS) ///
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