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    Physical address
    1100 West 49th Street
    Austin, Texas 78756-3199
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    Mailing address
    Center for Health Statistics
    Department of Health State Services
    Mail code: 1898
    Austin, TX 78741-9347

    Phone: (512) 776-7261 ext. 3144
    Fax: (512) 776-3255
    Email: gis@dshs.texas.gov


Geocoding is the first step in using locational data with geographic information system software. Examples of public health studies utilizing geocoded data include tracking the spread of infectious and environmentally caused diseases, identifying factors related to low birth weight, and linking client populations to provider locations.

Geocoding is the process of assigning coordinates, most commonly latitude and longitude, to a street address. For example:


Original Address     Geocoded Address      
Address ZIP   Address ZIP Latitude Longitude
1100 W 49th St 78756   1100 W 49th St 78756 30.8215 -97.735514

The coordinates represent the approximate location of the street address, but when it is not possible to locate the street address, the coordinates can represent the center of an area, commonly a ZIP code. Geocoding relies on two data sets, a reference street data set, which can include not only streets but also ZIP code boundaries, and the data containing the street addresses to be geocoded. If the street address data are not complete or correct or if the street reference files are not complete, an address may not geocode to street.



Last updated May 9, 2017