How are NHANES participants selected?

NHANES will contact the selected household and ask a short set of questions (age, race, and gender) about everyone in the household. A computer process randomly selects some, all, or none of the household members.

What is NHANES III?

The third National Health and Nutrition Examination Survey (NHANES III), conducted in 1988-1994, was 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.

What does NHANES measure?

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, physical examinations, and administers tests of physical activity and fitness that include children and adolescents.

Is NHANES population based?

Participant Involvement and Benefits. The National Health and Nutrition Examination Survey (NHANES) is a population-based survey designed to collect information on the health and nutrition of the U.S. household population. Participants are selected using a random sampling method.

What is a PSU in NHANES?

Four Stages of NHANES Sampling Procedure. Stage 1: Primary sampling units (PSUs) are selected. These are mostly single counties or, in a few cases, groups of contiguous counties. PSUs are selected with probability proportional to a measure of size (PPS).

Is NHANES a cohort study?

The NHEFS cohort includes all persons 25-74 years of age who completed a medical examination at NHANES I in 1971-75 (n = 14,407). It is comprised of a series of follow-up studies, four of which have been conducted to date.

How does NHANES sample?

The NHANES samples are not simple random samples. Rather, a complex, multistage, probability sampling design is used to select participants representative of the civilian, non-institutionalized US population.

Is NHANES a cross sectional study?

The NHANES has a long history, a cross-sectional design, and sample sizes in the range of 5,000 per wave.

How often is NHANES data collected?

2-year cycles
Continuous since 1999; data are publicly released in 2-year cycles. Estimates are calculated using one or more 2-year cycles.

Is NHANES cross sectional or longitudinal?

One prominent difference between the National Health and Nutrition Examination Survey (NHANES) and the other studies is that the latter follow people over time and thus have a longitudinal relationship with their participants, whereas NHANES is a cross-sectional survey of the U.S. population.