The current National Health and Nutrition Examination Survey (NHANES) is a continuous program starting in 1999. The survey interviews and examines a nationally representative sample of 5,000 persons each year. These persons are located in counties across the country, 15 of which are visited each year. No geographic location was released in order to protect the identification of respondents for the NHANES survey. State and county information could be obtained through the Research Data Center (RDC). It is desirable, however, to use a finer level of geography to spatially analyze the NHANES data and to answer various important research questions about the effect of geography on health. Therefore, NCHS has asked HUD to geocode (i.e., assign geographic codes to) the NHANES survey data for analytical use in the RDC every two year cycle.
HUD geocoded the 2005-2006 NHANES survey data to the 2000 census.
Specifically, HUD provided:
- Census block group, census tract, county, state, and all other census codes normally provided by the HUD Geocoding Service Center for each residential address.
- Latitude and longitude for each residential address.
2005-2006 NHANES Geocoding Summary:
Input Data Records Read (All SPs): 10,348
Census 2000 RC Values
"S" Street Match GCP rcds: 9,526
"9" ZIP+4 Match GCP rcds: 356
"5" ZIP Match GCP rcds: 466
Space (Nomatch) GCP rcds: 0
Census 2000 LVL Values
"R" "Rooftop" Level rcds: 9,526
"4" ZIP+4 Level records: 43
"B" Block Group LVL records: 313
"T" Tract Level records: 466
"2" ZIP+2 Level records: 0
"5" ZIP5 Level records: 0
"Z" ZIP Level records: 0
Space (Nomatch) LVL records: 0