Transportation Disadvantage Index: Progress towards developing a new community measure of child health access barriers

Particularly in health professional shortage areas, distance to travel and availability of transportation complicate healthcare access regardless of insurance status. We sought to identify areas where transportation barriers are particularly acute for children by developing a Transportation Disadvantaged Index. Using Texas State Health Department 2004-2006 hospital discharge data, a multiple regression design of admissions classified as ambulatory care sensitive conditions (ACSC) was used as proxy for children's healthcare access. We used ordinary least squares regression to identify predictors of non-emergent ACSCs by zip code in Travis County, Texas and six contiguous counties. Using Geographical Information System (GIS), we mapped the level and intensity of ACSCs by zip code. Covariates included ratio of automobiles to population, distance to nearest federally qualified health center (FQHC), percent of working population taking public transportation to work, urban/rural Census Bureau designation and socioeconomic characteristics. Of the 15,862 pediatric emergency department (ED) visits, 2,883 (18.1%) were classified as non-emergent ACSCs. Among children utilizing ED services for ACSCs, there were strong inverse relationships between ratio of automobiles to population (p<.013), percentage of working population taking public transportation to work (p<.004) and percentage of population living in rural zip codes, where travel distances are greatest (p<.028). The data suggest that greater travel distance to FQHCs and less available personal transportation are associated with greater ED utilization for ACSCs. Factors associated with transportation barriers can be identified and mapped using GIS. Policy makers can target these areas to improve availability of non-emergency medical transportation and deploy new healthcare resources.