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An Online Geographic Data Visualization Tool to Relate Preterm Births to Environmental Factors


The figure depicts 2 examples of data visualizations for the front-end site of the preterm birth visualization tool. The first displays two maps side by side. Each map shows the same census tract boundaries for an area of the city of Fresno. The map on the left depicts preterm birth rates. Data were unavailable for some census tracts. The map on the right depicts the total pollution score from the CalEnviroScreen pollution tool. The area encompassed by this figure has overall high pollution rates and moderate-to-high preterm birth rates. One specific census tract is highlighted in both maps demonstrating the map linkage capability of the tool. The second data visualization has 2 boxes. On the left it depicts all of Fresno County using Medical Service Study Area (MSSA) geographical units to show preterm birth rates throughout the county. On the right a histogram shows spontaneous preterm birth rates for each MSSA included in the map. The bar with the highest rate of spontaneous preterm birth is highlighted, and the corresponding MSSA is highlighted on the map on the left. A popup box gives further information about that MSSA with specific values of preterm birth and spontaneous preterm birth.

Figure 1.
A. Demonstration of the environmental pollution topic of an online geographic data visualization tool for exploring preterm birth in Fresno County, California, using linked maps. Different indicators can be selected for each map. B. The birth topic with overall preterm birth shown on the map and spontaneous preterm birth shown on the indicator histogram. Data elements are linked so that as selection of 1 data value occurs, the location of that data value is displayed on the map.

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The figure depicts 2 examples of data visualizations for the back-end site of the preterm birth visualization tool. In the top figure the indicator explorer feature is demonstrated showing a map of Fresno County on the left and a histogram on the right of a selected indicator, women who gave birth preterm (<37 weeks) and used WIC. Values in numbers for each MSSA are shown on the map on the left, and the histogram on the right depicts the same values in graphical format. The highest value is shown to be Fresno East Central with a value of 915. This MSSA is also highlighted on the map. The bottom figure shows the relationship explorer tab, which generates a correlation matrix visualized as a heat map for selected indicator values. Indicators related to risk score for preterm birth and race are shown. The heat map shows high positive correlation values and high negative correlation values. The map includes controls on the left of the screen for changing the correlations, the number of MSSAs included in the analysis, and the minimum correlation value to be included in the heat map.

Figure 2.
A. Demonstration of the indicator explorer feature of an online geographic data visualization tool to explore preterm birth in Fresno County, California. The indicator explorer feature allows mapping and side-by-side histogram evaluation of any of the hundreds of variables included in the back-end site. As one variable is selected, the relationship between that indicator and others can be viewed in alternate tabs. B. The relationship explorer tab, which builds correlation matrixes for selected indicators. Users can change color, specify the minimum number of geographical units that must be included, and specify the minimum correlation value.

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The opinions expressed by authors contributing to this journal do not necessarily reflect the opinions of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors’ affiliated institutions.

Page last reviewed: August 8, 2019