Geographic access to healthcare in houston using influenza emergency departent visits as a health indicator

Sophia Ali, The University of Texas School of Public Health


Little literature exists on geographic access barriers to primary care in urban areas. The objective of this ecologic study is to determine if an association exists between emergency department (ED) visits for influenza like illnesses (ILI) and physician density as well as certain demographic and socioeconomic factors in Houston, Texas. Physician density (number of physicians/1000 persons) and ILI density (number of ILI ED visits/1000 persons) were obtained for 138 zip codes from the Texas Medical Board and the Houston Department of Health and Human Services, respectively while demographic and socioeconomic factors were obtained from the 2010 census. Univariate analyses were conducted using spearman correlation and ANOVA. Using spearman, physician density was significantly negatively associated with ILI density ( rho=-0.17, p=0.04). Percent uninsured, below poverty, unemployed, black, and Hispanic were significantly positively associated with ILI density while median income, educational attainment, and percent white and Asian were significantly negatively associated with ILI density. The strongest association was with unemployment (rho=0.59). All associations were significant in ANOVA except physician density. Our findings suggest a possible negative correlation between physician density and ILI density, indicating that zip codes with high physician density may have lower density of ILI, but a larger sample size and a multivariate model are needed for further analysis.

Subject Area

Geographic information science|Public health|Epidemiology

Recommended Citation

Ali, Sophia, "Geographic access to healthcare in houston using influenza emergency departent visits as a health indicator" (2014). Texas Medical Center Dissertations (via ProQuest). AAI1568955.