UNDERSTANDING SPATIAL DISTRIBUTION OF ASTHMA USING A GEOGRAPHICAL INFORMATION SYSTEM Mohammad A. Rob Management Information Systems University of Houston-Clear Lake

Contents Introduction Geographic Information System (GIS) Asthma Epidemic: An Example Applications of GIS in Spatial Distribution of Asthma Business Geography: A New Discipline Conclusion

Introduction Geographic Information System (GIS) is used to make strategic decisions when data have spatial (geographical) distribution Government agencies use it for assessment and planning in areas such as housing, healthcare, land use, transportation, and environmental monitoring Businesses use it to locate optimum retail location and delivery route

Introduction Current corporate databases do not contain geospatial reference However, GIS tools can be used to add geographical coordinates to existing data Thus existing data can be presented on a map and make strategic decisions Major database vendors (Microsoft, IBM, Oracle, Informix) are adding a “spatial” data type to their enterprise database systems

Introduction The use of GIS tools require more knowledge of information technology than geography GIS datasets are already available through the Web Most organizations perform GIS analysis without getting involved with the mapping technology There are GIS technicians, analysts, programmers, and managers

Introduction Soon there will be GIS specialists like IT specialists in every organization Many IT specialists will become GIS specialists We discuss the basic principles and functionality of a GIS We also illustrate how GIS tools can be used to analyze and interpret user data using an example of asthma epidemiology

Geographical Information System (GIS) What is GIS? –GIS is a computerized system for input, storage, management, display, and analysis of data that can be precisely linked to a geographical location GIS datasets come as layers: –a layer for roads –a layer for rivers –a layer for zip code boundary –all within a particular geographical boundary

Geographical Information System (GIS) A layer may consists of a vector or raster Raster data types are images Vectors data types are defined by points, lines and polygons (boundary) –Points: hospitals, parks, and fire hydrants –Lines: Roads, highways, and rivers –Polygon: Zip code, county, state, and country A layer may consist of many features Several layers are combined to create a map

Major Roads and highways of Texas

County Boundaries of Texas

Superimposed Roads with County Boundaries

Expanded View: City of Houston

Geographical Information System (GIS) All features in a layer are stored in a shapefile Each shapefile has more than one file types associated with it: –one for the primary feature (points, lines, etc.) –one for the geometrical coordinates of the primary feature: (x, y) or (x1, y1 -- x2, y2) –one for the geographical coordinate system (longitude, latitude) –all sharing the same filename

Geographical Information System (GIS)

Each GIS layer has two views: –a map view –a data view The map acts as visual representation of data The data view can be used to: –to create a smaller dataset or map –to combine with user data to create a new layer (as long as there is a common attribute between the GIS data and the user data)

GIS Layer: Map View

GIS Layer: Data View

Geographical Information System (GIS) Most commonly used GIS tool is ArcView from ESRI (Environmental Systems Research Institute) –It uses a geodatabase to store all features –Can be used as a desktop or multi-user database Many federal, state, and local government agencies publish GIS data in the ArcView’s shapefile format These files can be downloaded from the Web

Geographical Information System (GIS)

Asthma Epidemic: An Example Asthma became a public health concern, especially among children in the U.S. –About 17.3 million Americans have asthma –More than 5000 people die from asthma per year –Asthma prevalence among children (0-17 years) increased by ~ 5% each year during –African Americans suffer more than Caucasians –Females suffer more than males

Asthma Epidemic: An Example

Applications of GIS: Spatial Distribution of Asthma Most of the asthma data come from hospitalization records or surveying a localized population These data do not contain any spatial or geographical coordinate, but use zip code However, they can be joined with a spatial dataset such as a zip code layer to create a asthma layer Zip code from the two datasets can be used as a join parameter

Asthma Study of New York City Asthma data came from a survey of middle- and high schools students in the NY City The students were in the age group of years About 4300 datasets were collected in two years from various boroughs of the city Data were summarized by zip code, borough, gender, and race ArcView GIS software was used for maps

Results: Total and Gender

Results by Race

Results by Borough

Summarized Data by Zip Code Zip CodeTotal SurveyedNum Of Asthmatics Percent Asthmatics

Resultant Dataset After Join on Zip Code: New York City

New York City Zip Code Layer

Map View of Resultant Dataset: NY City

Resulting Map Displaying the Zip Codes Surveyed

Overlaying of Asthma and NY City Layers

New York City Poverty

Comparison of Asthma and Poverty

GIS in Business GIS can be used to: –Optimize sales territories and delivery route to balance workload and minimize travel –Display sales forecasts utilizing customer demographic trends –Business site selection utilizing customer demographic trends –Evaluate business acquisition opportunities by knowing business composition and consumer consumption patterns in the locality

Map Customer Locations Create a "pin map" of where your customers live Find out what parts of town you draw customers and where to advertise

Identify Your Trade Area Map your customers to see what your trade area is Compare your customers with the market potential to see your market penetration

Target Your Advertising Given your trade area, and your customer profile, you can focus advertising to the places and media that are most likely to hit your target market

Business Geography: A New Discipline The combined use of computer-mapping, Internet, database technologies, and location- allocation modeling techniques will become a particularly important set of skills for many business students whose first jobs after graduation involve real estate, urban, demographic, retail, marketing, environmental, transportation, international trade or investment analyses. A new discipline called “Business Geography” is evolving in many business schools across the country

Conclusion We have provided a brief overview of a Geographical Information System GIS uses various layers to create a map and each layer has two views: a dataset and a map Most layers are available from local, state, and federal government agencies Asthma epidemiology is used as an example to illustrate how user data can be combined with GIS data and make further decisions for research or healthcare planning We have also highlighted on Business Geograhy, an evolving program in business schools