Geographic Information Systems (GIS)

Spatial Database Management, Mapping, and Analysis

GIS tools support spatial database management, visualization and mapping, and analysis. Many public and private health agencies manage databases, usually stored and viewed as tables, describing the health status and health service utilization of individuals. GIS software functions can be used to make these data mappable at a high level of geographic disaggregation. The objects—for example, patients with specific health problems and the health facilities where they receive treatment—whose attributes are described in a health database can also be assigned spatial dimensions and attributes. Objects represented as points, such as the place where a clinic or patient resides, have position in space, and these positions are recorded using longitude and latitude coordinates or coordinates from one of many other coordinate systems used for mapping. Lines are created by connecting the points; these lines can be routes for home-delivered healthcare services and similar factors. Health-planning districts might be represented as areas, objects formed by closed, connected lines. These types of spatial data are referred to as object, or entity, data. Vector databases are collections of discrete objects modeled as points, lines, or areas whose locations and other attributes are described. Vector databases that describe property parcels are sometimes referred to as cadastral databases. These databases are often used for local public health service applications such as drinking water regulation and emergency response.

GIS software functions enable users to import tabular data and to create and edit points, lines, and areas representing objects of interest. Tables of data containing X, Y coordinates, such as longitude and latitude values, captured using global positioning system (GPS) technology can be added to a GIS and converted to point databases. The United States and other nations use address-matching geocoding tools in GIS software to map locations of cases of disease, healthcare facilities, and other points of interest. The Healthy People 2010 initiative of the U.S. Department of Health and Human Services (HHS) revised its objective for the use of geocoding in health data systems to achieve 100% nationwide use of GIS by 2010 by increasing the proportion of major national health data systems that use geocoding.

...