Predictors of Regional Medicare Expenditures for Otolaryngology Physician Services

Objective: To describe geographic variation in spending and evaluate regional Medicare expenditures for otolaryngologist services with population-and beneficiary-related factors, physician supply, and hospital system factors. Study Design: Cross-sectional study. Methods: The average regional expenditures for otolaryngology physician services were defined as the total work relative value units (wRVUs) collected by otolaryngologists in a hospital referral region (HRR) per thousand Medicare beneficiaries in the HRR. A multivariable linear regression model tested associations with regional sociodemographics (age, sex, race, income, education), the physician and hospital bed supply, and the presence of an otolaryngology residency program. Results: In 2012, the mean Medicare expenditure for otolaryngology provider services across HRRs was 224 wRVUs per thousand Medicare beneficiaries (standard deviation [SD] 104), ranging from 31 to 604 wRVUs per thousand Medicare beneficiaries. In 2013, the average Medicare expenditures for each HRR was highly correlated with expenditures collected in 2012 (Pearson correlation coefficient .997, P =.0001). Regional Medicare expenditures were independently and positively associated with otolaryngology, medical specialist, and hospital bed supply in the region, and were negatively associated with the supply of primary care physicians and presence of an otolaryngology residency program after adjusting for other factors. The magnitude of associations with physician supply and hospital factors was stronger than any population or Medicare beneficiary factor. Conclusion: Wide variations in regional Medicare expenditures for otolaryngology physician services, highly stable over 2 years, were strongly associated with regional health system factors. Changes in health policy for otolaryngology care may require coordination with other physician specialties and integrated hospital systems.