Seeing patterns to drive actionable insights

 Chad Mitchell
Data Scientist

Chad-Mitchell-250x250“We are largely unconscious of the centrality of maps in contemporary Western life precisely because they are so ubiquitous, so profoundly constitutive of our thinking and our culture. We are bombarded by maps in our newspapers, on our televisions, in our books, and in our getting around in the modern world. The cartographic trope is all pervasive. We talk of cognitive maps, mental maps, genetic maps, or of mapping the mind and mapping the human genome. Minds, languages, cultures, laws, and environments are [all] described as maps.” (Turnbull 2000, pp 93).

London, in the mid 1850’s, was a bustling city of about 2.5 million people living in close proximity to one another with basically no sewage infrastructure or waste management system. It provided the perfect environment for infectious diseases like cholera to spread. Although the city suffered recurring cholera outbreaks during the decade, one of the worst outbreaks occurred in 1854 within the Soho district. In the span of about a week, roughly 500 people died, and no one knew why the disease was spreading.

Epidemiologist, John Snow, began constructing a map and realized that the deaths were clustered around one particular water pump on Broad Street (now Broadwick). After testing samples from the area and confirming the presence of an unknown bacterium, Snow persuaded the authorities to remove the pump’s handle. Though he was heavily resisted, shortly thereafter the outbreak settled and the cause was known, forever changing public health in London and around the world (Johnson 2006).


Section of John Snow’s map centered on Broad street – black bars represent cholera deaths

Maps and geospatial data have been used for hundreds of years in the healthcare field to provide insights about human complexity and to contribute to the conversation on how we can change behavior to improve public health. We at NextHealth are actively integrating geospatial technologies into several of our products, most recently including an interactive choropleth map (similar to a heatmap) and a collection of distance-based metrics used for predictive analytics.

What is a Choropleth Map?

Choropleth maps date back to the 1820’s and have been used ever since to visualize variations in data, such as population density, across geographic units (e.g. countries, states, zip codes). Although similar to heatmaps, they are distinct. In general, choropleths are helpful for identifying potential hot spots of activity, comparing geographic regions, and spotting intriguing patterns that might otherwise be missed using traditional statistics and data visualization techniques.

As mentioned above, we will soon be releasing an update to the NextInsight element of the platform that includes an interactive choropleth map with dozens of variables to compare.


Geospatial Predictors

In addition to the new interactive choropleth map, we have also developed a variety of geospatial variables to support our predictive analytics capabilities. Distance-based variables can be extremely helpful in understanding complex healthcare behaviors like avoidable ER visits and out-of-network utilization.

A sample of the distance-based metrics we have developed include: average distance a member has travelled to receive care, entropy (i.e. uncertainty) of the frequency across locations a member has travelled for care (Shannon), and several metrics derived from the distance between how far a member would travel for out-of-network care and how far they would have to travel to the nearest in-network provider.

To find out more about what we are doing with feature engineering, see the NextData page.

In summary, geospatial technology has supported healthcare innovation for a long time, often being instrumental in major discoveries. We at NextHealth are constantly seeking new ways to derive valuable and actionable insights for our clients, helping them find the signal in the noise, and driving sustained improvements in their members’ healthcare through targeted, personalized interventions at the right time.

For a demo of the platform or to learn more about how NextHealth can help drive medical cost reductions in your business, please contact us.


  • Johnson, Steven, (2006). “The Ghost Map: The Story of London’s Most Terrifying Epidemic, and How It Changed Science, Cities, and the Modern World”.
  • Shannon, Claude E. (1948). “A Mathematical Theory of Communication”. Bell System Technical Journal 27 (3): 379-423. doi:10.1002/j.1538-7305.1948.tb01338.x
  • Turnbull, David. (2000). “Masons, Tricksters, and Cartographers: Comparative studies in the sociology of scientific and indigenous knowledge”. Routledge, London & New York.