Use of Density-Equalizing Cartograms to Visualize Trends and Disparities in State-Specific Prevalence of Obesity: 1996-2006

Objectives. We used cartograms to visually communicate the state-specific prevalence of obesity and its association with socioeconomic variables over time to benefit and inform decisions by national health policymakers who address geographic and social inequities in health. Methods. We generated density-equalizing maps, known as cartograms (in which geographic regions are sized in proportion to some variable), that illustrate indicators of population and educational attainment. We also provide an innovative presentation of the obesity choropleth map (which presents values for areas by shading). Results. The maps depict the absolute burden of obesity, the inverse association between obesity and education, and geographic patterns in the prevalence of obesity over time. Conclusions. The prevalence of obesity in the United States continues to increase. These cartograms can help stakeholders interpret surveillance data and their relation to demographic and socioeconomic characteristics to inform decisions. (Am J Public Health. 2009;99:308-312. doi:10.2105/AJPH.2008.138750)