Quantitative Analysis of Practice Size Consolidation in Radiation Oncology: A Trend Toward Bigger and Fewer Practices.

PURPOSE: There is evidence of practice consolidation in US health care in recent years. To our knowledge, a detailed quantitative study of recent changes in radiation oncology practice size has not been performed. We aim to evaluate radiation oncology practice size changes between 2012 and 2020 in the United States. MATERIALS AND METHODS: Using the Medicare Physician Compare Database, we identified practices employing radiation oncologists using their taxpayer identification number and individual radiation oncologists using their national provider identifier. We grouped individual radiation oncologists into categories by practice size (which includes the number of physicians of all specialties) and compared the number of radiation oncologists in each category between 2012 and 2020. Further analyses by US geographic census region, single-specialty practice, academic practice, and high- and low-population density areas were performed. RESULTS: Between 2012 and 2020, the total number of practicing radiation oncologists increased by 9%, and the number of practices employing radiation oncologists decreased by 11.5%. The number of radiation oncologists in practices of size 1 to 2, 3 to 9, 10 to 24, and 25 to 49 decreased by 3.7%, 4.7%, 4.9%, and 2%, respectively, and the number of radiation oncologists in practices of size 50 to 99, 100 to 499, and 500+ increased by 1.4%, 2.1%, and 11.8%, respectively (all 500+ practices are multispecialty groups). The increase in practice size was significant in all regions, for single-specialty and multispecialty practices, academic and nonacademic practices, and for practices in high-, middle-, and low-population density areas (P < .05 for all comparisons). The proportion of single-specialty practices has decreased significantly (P < .001), and the proportion of academic practices increased significantly (P = .004). Additionally, the proportion of practices and physicians in high- and low-population density regions remained stable during this period (P > .05). CONCLUSIONS: Our analysis suggests that practice size consolidation has occurred within the US radiation oncology workforce from 2012 to 2020. The impact of this consolidation on quality, cost, and patient access deserves further attention.