title: Variation in low food access areas due to data source inaccuracies.
abstract: Several spatial measures of community food access identifying so called "food deserts" have been developed based on geospatial information and commercially-available, secondary data listings of food retail outlets. It is not known how data inaccuracies influence the designation of Census tracts as areas of low access. This study replicated the U.S. Department of Agriculture Economic Research Service (USDA ERS) food desert measure and the Centers for Disease Control and Prevention (CDC) non-healthier food retail tract measure in two secondary data sources (InfoUSA and Dun & Bradstreet) and reference data from an eight-county field census covering169 Census tracts in South Carolina. For the USDA ERS food deserts measure accuracy statistics for secondary data sources were 94% concordance, 50-65% sensitivity, and 60-64% positive predictive value (PPV). Based on the CDC non-healthier food retail tracts both secondary data demonstrated 88-91% concordance, 80-86% sensitivity and 78-82% PPV. While inaccuracies in secondary data sources used to identify low food access areas may be acceptable for large-scale surveillance, verification with field work is advisable for local community efforts aimed at identifying and improving food access.
authors.affiliation: Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA.
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Ma
authors.affiliation: Department of Geography, University of South Carolina, Columbia, SC, USA.
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Battersby
authors.affiliation: College of Education, University of South Carolina, Columbia, SC, USA.
authors.forename: Bethany A
authors.initials: BA
authors.lastname: Bell
authors.affiliation: Center for Research in Nutrition and Health Disparities, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Hibbert
authors.affiliation: Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA.
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Barnes
authors.affiliation: Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA ; Center for Research in Nutrition and Health Disparities, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA.
authors.forename: Angela D
authors.initials: AD
authors.lastname: Liese
keywords: Dun & Bradstreet; field census; food desert; food environment; infoUSA; policy