Five Essential Properties of Disease Maps

In Five Essential Properties of Disease Maps, the authors describe the pros and cons of the essential properties of disease maps and how to improve them. 

1.     “Control the population basis of Spatial Support for estimates of Rates”


 In this step the authors describe how the population residing within geographic areas affects the calculation of disease rate.  For example they describe how Iowa is relatively small both in size and county boundary wise, but the populations differ greatly in boundaries showing varying levels across the map. Contributing to this variation also includes social, economic, and physical characteristics. 

2. “Display Rates Continuously through Space” 

This step describes the struggle of representing how disease patterns are shown in maps that accurately show real life risk patterns. Significant difficulties include geographic features. 

3  “Provide Maximum Geographic Detail Across the Map"
 In disease maps detail around boundaries is often lost due to rural vs urban characteristics.

 4. "Consider Directly and Indirectly Age-Sex Adjusted Rates"

The traditional American way to use direct age adjustment is to multiply local disease rates by standard population weights. The authors believe that this way is not as good as the three-step algorithm that finds the sum of the weighted rates through the directly age adjusted rate.

 5. "Visualize Rates within a Relevant Place Context to Enhance" 

Interpretation The last step describes allowing more maps to be placed out in the public, so that the public can better there health through the help of these maps.

As shown below all five steps done correctly.

 Kirsten M. M. Beyer, Chetan Tiwari & Gerard Rushton (2012): Five Essential Properties of Disease Maps,
 Annals of the Association of American Geographers, 102:5, 1067-1075