Geographic analysis of the radiation oncology workforce

Purpose: To evaluate trends in the geographic distribution of the radiation oncology (RO) workforce. Methods and Materials: We used the 1995 and 2007 versions of the Area Resource File to map the ratio of RO to the population aged 65 years or older (ROR) within different health service areas (HSA) within the United States. We used regression analysis to find associations between population variables and 2007 ROR. We calculated Gini coefficients for ROR to assess the evenness of RO distribution and compared that with primary care physicians and total physicians. Results: There was a 24% increase in the RO workforce from 1995 to 2007. The overall growth in the RO workforce was less than that of primary care or the overall physician workforce. The mean ROR among HSAs increased by more than one radiation oncologist per 100,000 people aged 65 years or older, from 5.08 per 100,000 to 6.16 per 100,000. However, there remained consistent geographic variability concerning RO distribution, specifically affecting the non-metropolitan HSAs. Regression analysis found higher ROR in HSAs that possessed higher education (p = 0.001), higher income (p < 0.001), lower unemployment rates (p < 0.001), and higher minority population (p = 0.022). Gini coefficients showed RO distribution less even than for both primary care physicians and total physicians (0.326 compared with 0.196 and 0.292, respectively). Conclusions: Despite a modest growth in the RO workforce, there exists persistent geographic maldistribution of radiation oncologists allocated along socioeconomic and racial lines. To solve problems surrounding the RO workforce, issues concerning both gross numbers and geographic distribution must be addressed.