Sample design and estimation procedures for a national health examination survey of children.

The Health Examination Survey is one of the major survey programs employed by the National Center for Health Statistics to obtain information about the health status of the U.S. population. It is a part of the National Health Survey, authorized in 1956 by the 84th Congress as a continuing Public Health Service activity. The National Health Survey employs three different survey programs to accomplish its objectives. One of these is the Health Interview Survey in which persons are asked to give in-formation related to their health or to the health of other household members. The second program, Health Resources, obtains health data and health resource and utilization information through surveys of hospitals, nursing homes, and other resident institutions and through the entire range of personnel in the health occupations. The third major program is the Health Examination Survey (HES), The Health Examination Survey collects data from samples of the civilian, noninstitutional population of the United States and, by means of medical and dental examinations and various tests and measurements, undertakes to characterize the population under study. This is the most accurate way to obtain diagnostic data on the prevalence of certain medically defined illnesses. It is the only way to obtain information on unrecognized and undiagnosed conditions-in some cases, even nonsymptomatic conditions. It is also the only way presently available to obtain distributions of the population by a variety of physical, physiological, and psychological measurements. Although the sample is designed primarily to estimate the prevalence of specified health and health-related conditions in the population, the design also makes possible the study of relationships of the examination findings to one another and to certain demographic and socioeconomic factors.