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Hagland, M. 2004. “Harnessing Efficiency.” Healthcare Informatics Online. http://www.healthcare-informatics.com/issues/2004/02_04/cover.htm#workflow (no longer available).
Johnson, M., W. L. Gorr, and S. Roehrig. 2005. “Location of Service Facilities for the Elderly.” Annals of Operations Research 136, no. 1: 329 – 49.
Kennedy, E. 2004. “Statement on the Introduction of the Health Care Modernization, Cost Reduction, and Quality Improvement Act”. http://kennedy.senate.gov/~kennedy/statements/04/05/2004513C28.html (no longer available).
Protti, D. J. 2005. “The Use of Computers in Health Care Can Reduce Errors, Improve Patient Safety, and Enhance the Quality of Service: There is Evidence.” Special Report: IT in the Health-Care Industry. The Economist 65 (April 30, 2005). http://www.connectingforhealth.nhs.uk/worldview/protti2 (no longer available).
Chapter 2
Visualizing health data
Objectives
• Visualize breast cancer mortality by US county
• Understand the composition of GIS map layers
• Learn how to navigate using zooming, panning, and bookmarks
• Understand the connection between visual map features and tabular data
• Learn how to select subsets of map features for processing
• Learn how to find map features
• Use data sorting and labeling to produce information
Health-care scenario
According to the National Cancer Society, breast cancer remains the most frequently diagnosed cancer in women in the United States. Determining top geographic areas where breast cancer deaths occur may lead health officials to provide better targeted screening or interventions.
Solution approach
You are just starting to use ArcGIS, so this chapter focuses on the basics of understanding and using GIS. To begin, you will work with an existing GIS document that you will open in ArcMap and modify by adding and symbolizing a map layer. Once the map document is in usable form, you will explore the map and associated attribute data using several GIS tools to do the following:
• Zoom, pan, and set spatial bookmarks to get close-up views of the map in selected areas of the United States
• Find and identify features and access feature attribute data to get information
• Select subsets of map layers to work with them and sort records to identify top cancer counties
• Label and annotate to add information to maps
Tutorial 2-1
Manipulating layers in a map document
In the first part of this chapter, you will learn the basics of the ArcMap software package. You will begin by opening an existing map document, and then learn how to add and manipulate map layers.
Start ArcMap and open an existing map document
1 On the taskbar, click Start and then All Programs > ArcGIS > ArcMap 10.2
2 Browse through the Maps folder, select Tutorial2-1.mxd, click Open, and click OK if prompted by a warning on VBA code. This map of US cities and states has two map layers already included, renamed, and symbolized. The first layer is Major US Cities (with population over 100,000). The second layer is Breast Cancer Deaths by State. We downloaded this data from the National Cancer Institute’s Cancer Mortality Maps website, http://www3.cancer.gov/atlasplus. This site provides valuable information about cancer mortality in the United States during the time period 1950 – 2004, based on data obtained from the National Center for Health Statistics (NCHS), the federal government’s principal vital- and health-statistics agency. If you wish to obtain other cancer statistics, visit this site or other websites such as http://www.cancer.gov/, http://seer.cancer.gov/, and http://wonder.cdc.gov/ (See facing page.)
Add a layer
You can add additional map layers to your map for more detailed analysis. For example, the National Cancer Institute collects cancer data by county as well as by state. You can add a layer of data showing the breast cancer mortality rates and the number of deaths per county. This data was saved by the authors as a file geodatabase feature class, which contains polygons for counties and related data on death rates.
1 Click the Add Data button .
2 In the Add Data dialog box, click the Connect To Folder button .
3 In the Connect to Folder dialog box, browse to Computer, click the drive where you installed the GISTHealth data (for example, C:\), and click OK. You only need to browse to the root drive and not go beyond this point. Once this connection is made, you can easily browse to any folder on this computer drive. If your data is stored on an external drive such as a jump drive, you will need to connect to that drive.
4 In the Add Data dialog box, browse to \EsriPress\GISTHealth\Data\NCI.gdb, click the BreCounty layer, and click Add.
ArcMap chooses a random color for the counties layer. You will change the color later.
Change the layer display order
Changing a layer’s display order is important because features may be covered up by other features in your map. ArcMap draws map layers from the bottom up, so if larger features are on top of smaller features, the smaller ones will not display.
1 Click the List By Drawing Order button, and then in the table of contents, press and hold the left mouse button on the Major U.S. Cities layer.
2 Drag the Major U.S. Cities layer to the bottom of the table of contents. Because the cities layer is now drawn first, its points are covered up by the states and counties layers and cannot be seen.
3 Drag the Major U.S. Cities layer back to the top of the table of contents. Because the cities layer is now drawn last, its points can again be seen.
YOUR TURN
Drag the BreCounty layer to the bottom of the list and observe what happens. Then drag it back to the middle of the three layers.
Rename a layer
You will notice that when you initially add a layer, ArcMap uses the name of the feature class as the default name of the layer in the table of contents. You will often want to change the name of the layer to a label that is easier to understand.
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