Geospatial and Socioeconomic Disparities in Access to IR Care in the United States

Purpose: To determine and analyze the geographic distribution of interventional radiologists in the United States to identify populations with decreased access to interventional radiology (IR) care. Materials and Methods: The Society of Interventional Radiology public database was reviewed for practicing interventional radiologists in all cities within the United States. U.S. Census data were used to acquire county-level data sets on poverty, population, unemployment, median household income, education, and racial diversity. Odds ratios were calculated for access to IR care between the 75th and 25th percentiles for each population variable. Counties with interventional radiologists were compared with those without for each variable using t-tests. Quantum Geographic Information System was used to map the distribution of interventional radiologists. Results: A total of 2,989 U.S. interventional radiologists were found to be operating in 15.5% (n = 487) of all counties. Almost one-third (31.2%) of the country's population did not have access to an interventional radiologist within their county. The mean interventional radiologist-to-population ratio was 0.305 per 100,000 people. The mean median income among counties with interventional radiologists was greater at $67,649 compared with $53,528 among counties without (P < .05). In addition, a mean of 31.3% of the population had a college degree in counties with interventional radiologists versus 20.3% in other counties (P < .001). Higher mean percentages of African Americans, Pacific Islanders, and Hispanics were observed in counties with interventional radiologists, at 13.1%, 0.232%, and 13.7%, respectively (P < .05). Conclusions: Interventional radiologists are disproportionately distributed, with higher densities of radiologists practicing near urban areas. Access is also limited to counties with higher incomes and a greater percentage of citizens with a college education.