Wednesday, November 14, 2018

Preventable Health Risks in the USA

Smoking, Obesity & Drinking is an Esri story map which visualizes the rates of three preventable health risk factors at the county level in the USA. It includes choropleth maps which reveal the rates of smoking, obesity and excessive drinking in every American county. Smoking, Obesity and Drinking is also a consummate lesson in how the story map format can be used to lead the user by the hand through complex visualizations of data.

Smoking, Obesity & Drinking uses bivariate (and trivariate) maps to try to examine the relationships between smoking, obesity & excessive drinking. Bivariate maps are used in the story map to identify areas where two or more of these three health risk factors might be anomalously high (or low). One disadvantage of bivariate maps is that they can be difficult to read. The wider range of colors representing combined values introduces more complexity, especially when compared to more simple single variable choropleth maps. However the Smoking, Obesity and Drinking story map overcomes any confusion that these bivariate maps might cause by first walking the user through each of the three health risk factors individually, each on their own single variable choropleth maps.

Not only does Smoking, Obesity & Drinking explore each of these three risk factors separately on its own choropleth map it also singles out and highlights those counties in which these factors are especially prevalent. Therefore when the bivariate maps are introduced the user has already been led through how to read much of the data. The story map also then proceeds to lead the user through the anomalous joint health risk factors revealed by the bivariate maps themselves.

In its conclusion Smoking, Obesity & Drinking introduces yet another degree of complexity by attempting to show all three health factors on one trivariate map. To try to make this trivriate map legible three foundational color hues are used to represent each of the three health risk factors. Even so it is still nearly impossible to create a comprehensible legend in a two dimensional space explaining the full range of values represented by the mixing of these three colors. Smoking, Obesity & Drinking overcomes this final problem with the clever solution of annotating the map itself, explaining some of the regional hues revealed on the trivariate map of American preventable health risks.

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