Fig. 2.
Heat map of county-level Spearman correlations between two measures of rural–urban status (population density and Rural–Urban Commuting Area [RUCA]) and measures of social determinants, overall and by US Census region. Red and pink boxes indicate positive associations, and blue areas indicate negative associations. Boldface indicates statistically significant correlation. RUCAs are available from the US Department of Agriculture and are a composite measure of population density, urbanization, and daily commuting time abstracted from the American Community Survey