National Health Survey, 2012
The National Health Interview Survey (NHIS) is a multi-purpose health survey
conducted by the National Center for Health Statistics (NCHS), Centers for Disease Control and Prevention (CDC), and is the principal source of information on the health of the civilian noninstitutionalized household population of the United States. The NHIS has been conducted continuously since its beginning in 1957. Public use data files are released on an annual basis.