B8

Introduction: Accessibility to mammography or other health care facilities in urban areas may pose a burden for minorities and low-income urban residents who depend on public transportation.
 Objective: To characterize the 282 census tracts in the Atlanta, Georgia Metropolitan Area with a transportation-based index based on selected 2000 U.S. Census variables.
 Methods: Census variables under consideration included: the percent of households without available vehicle (automobile access), percent living below poverty, percent minority, median family income, proportion age 25 and older without high school education, and percent civilian unemployed. Two methodologic approaches were taken. In the first, each of the selected census variables was ranked from highest to lowest in each tract for all Metro Atlanta census tracts. A percentile rank was then calculated for each variable in each tract. The percentile rank for a specific variable places that variable in the distribution of the scores across the Metro Atlanta census tracts. The ranks of variables for each tract were summed and an overall percentile rank was then calculated for the sum. In the second approach, the counts of individual variables for each tract with a percentile rank of ninety or higher were summed for a final score. We further explored the concordance of census tract rankings between an index based on one variable (automobile access) vs. an index based on all demographic variables using rank order correlation statistic. We also examined automobile access rankings by minority status.
 Results: Maps displaying the percentile ranks and summed 90th percentile counts will be presented for comparison. We present the concordance of census tracts using a single variable (automobile access) compared with an index using the demographic variables.
 Conclusion: This study will provide a description of the Atlanta Metropolitan Area census tracts where residents potentially face the most serious transportation barriers to care. This characterization will provide the starting point and demographic layer for a geographic information system (GIS) that includes mammography facility locations, public transportation routes, and roadways, for an analysis of time and distance barriers to mammography facilities.

First AACR International Conference on the Science of Cancer Health Disparities-- Nov 27-30, 2007; Atlanta, GA