Table 1.

Overview of the sources of study factor data.

	NHANES	NHIS	BRFSS
Target population	Civilian, noninstitutionalized US population	Civilian, noninstitutionalized US population	US adult population
Sampling approach	Multistage, probability sampling	Multistage, probability sampling	Sampling based on landline (and also cellular telephone numbers since 2011)
Data collection	Household interviews and physical examinations	Household interviews	Telephone interviews
Included surveys	NHANES I (1971-1974), NHANES II (1976 to 1980), NHANES III (1988 to 1994), continuous NHANES (1999-2016)	NHIS (1976, 1977, 1985, 1987, 1988, 1990-1995, and 1997-2016)	BRFSS (1984-2016)

NHANES=National Health and Nutrition Examination Surveys; NHIS=National Health Interview Surveys; BRFSS=Behavioral Risk Factor Surveillance System;