TABLE 1.

NHANES sample design

					Continuous NHANES
Characteristic	NHANES I: 1971–1974	NHANES II: 1976–1980	Hispanic NHANES: 1982–1984	NHANES III: 1988–1994	1999–2006	2007–2010	2011–2014
Ages examined	1–74 y	6 mo–74 y	6 mo–74 y	≥2 mo	All ages	All ages	All ages
Mean number of sample persons per eligible household	1	1	2.71	2.03	2.02	2	2
Geographic areas covered	United States (excluding Alaska and Hawaii)	United States	Mexican American persons, Southwestern United States; Puerto Rican persons, New York, New Jersey, Connecticut; Cuban persons, Dade County, Florida	United States	United States	United States	United States
Study locations, n	100	64	17 in Southwest; 9 in New York, New Jersey, Connecticut; 4 in Dade County, Florida	89	117	60	60
Domains oversampled	Low income (at or below 100% of federal poverty level): children aged 1–5 y; women aged 20–44 y; persons aged 65–74 y	Low income (at or below 100% of federal poverty level): children aged 6 mo–5 y; persons aged 60–74 y	Persons aged 6 mo–19 y and 45–74 y	Mexican American persons; black persons; children aged <1 y; adults aged ≥60 y	Mexican American persons; black persons; low-income white and other persons (at or below 130% of federal poverty level); adolescents aged 12–19 y; adults aged ≥70 y; supplemental sample of pregnant women	Hispanic persons; non-Hispanic black persons; low-income non-Hispanic white and other persons (at or below 130% of federal poverty level); non-Hispanic white and other persons aged ≥80 y	Hispanic persons; non-Hispanic black persons; non-Hispanic nonblack Asian persons; low-income non-Hispanic nonblack non-Asian white and other persons (at or below 130% of federal poverty level); adults aged ≥80 y
Selected persons, n	28,043	27,801	15,924	39,695	50,939	26,215	27,631
Persons interviewed in the household, n (%)	27,758 (99)	25,286 (91)	13,689 (86)	33,994 (86)	41,474 (81)	20,686 (79)	20,491 (74%)