Residential Segregation and the Availability of Primary Care Physicians

Objective To examine the association between residential segregation and geographic access to primary care physicians (PCPs) in metropolitan statistical areas (MSAs). Data Sources We combined zip code level data on primary care physicians from the 2006 American Medical Association master file with demographic, socioeconomic, and segregation measures from the 2000 U.S. Census. Our sample consisted of 15,465 zip codes located completely or partially in an MSA. Methods We defined PCP shortage areas as those zip codes with no PCP or a population to PCP ratio of >3,500. Using logistic regressions, we estimated the association between a zip code's odds of being a PCP shortage area and its minority composition and degree of segregation in its MSA. Principal Findings We found that odds of being a PCP shortage area were 67 percent higher for majority African American zip codes but 27 percent lower for majority Hispanic zip codes. The association varied with the degree of segregation. As the degree of segregation increased, the odds of being a PCP shortage area increased for majority African American zip codes; however, the converse was true for majority Hispanic and Asian zip codes. Conclusions Efforts to address PCP shortages should target African American communities especially in segregated MSAs.