Office of Health Information and Policy
Geographic Information Systems (GIS) Team
GIS, an acronym for geographic information system, is used to process, edit,
query, analyze, and visualize spatial data and their attributes. The power of
GIS is its ability to identify relationships among features on different map
layers based on where they are located in relationship to one another. A GIS
answers simple questions such as “How many toxic release sites are within
a mile of my home?” It also helps in more complex spatial analyses, such
as determining environmental factors involved in the spread of disease or in
developing a model for predicting census tracts at high risk for child abuse
based on perinatal risk factors.
GIS is a core analytical method for public health. Its applications are essential
for effective health status assessment, health planning, program evaluation,
and surveillance. For DHR agencies and organizations, the OHIP GIS Team provides maps and spatial analysis, geocoding, and spatial data.
Maps and Spatial Analysis
The Office of Health Information & Policy (OHIP) maintains a suite of tools,
known as OASIS, for performing data analysis relevant to public health and public
policy. With the OASIS GIS Mapping Tool, users can create and print maps including
mortality, morbidity, and maternal/child health indicators.
Maps are used in different ways. The most familiar method of map use is to
present information, such as the route from one place to another, the location
of health care facilities, or the rate of teen pregnancy by census tract. Maps
are also used for the exploration of spatial data through visual analysis, or
visualization. For example, it is much easier to use a map to see that two spatial
data layers, such as demographic clusters and teen pregnancy rates, appear to
be geographically correlated than to use a list or a table. Recognition of patterns
and relationships through visualization leads to the next step in the analytical
process, which is to apply spatial statistical methods to verify, quantify,
and determine the significance of these relationships
For Georgia Department of Public Health (DCH) agencies and organizations, OHIP also
provides limited custom mapping services for presentation, as well as assistance
with analysis and spatial statistics.
Recent examples of custom map presentation
Confidentiality and Geocoded Health Data - 2007 GPHA Poster Presentation (27 Mb)
Exploring the Spatial Relationship Between Fetal Death Distribution and Toxic Release Inventory Sites in Georgia - 2007 GPHA Poster Presentation (6 Mb)
Identifying perinatal risk factors for infant maltreatment: an ecological approach. Yueqin Zhou, Elaine J Hallisey and Gordon R Freymann. International Journal of Health Geographics, 2006, 5:53.
Child Maltreatment Risk in
Georgia. Elaine J. Hallisey and Gordon R. Freymann. GIS in State Government, Volume 1, 2005. ESRI.
Demographic Clusters and Substantiated Infant Abuse and Neglect in Atlanta, 2000-2002.
Stroke Mortality is Related to Hospital Readiness in a Stroke Belt State. (15 Mb)