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Using Geographic Methods to Understand Health Issues

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Figure 5. Definition of Medical Service Area (MSA) Based on Patient Origin: Commitment Index (CI)

Description for figure given below

A choroplethic or shaded map (bottom) is used to display numeric information (top). This example gives a graphic depiction of hospital admissions from the hospital's perspective; shaded portions indicate the ZIP Code areas that contribute the first 60 percent of the hospital's patients.

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