Sex-Based Differences in Medicare Reimbursements among Ophthalmologists Persist across Time

Purpose: To evaluate differences in Medicare reimbursements between male and female ophthalmologists between 2013 and 2019.

Design: Retrospective cohort study.

Participants: Ophthalmologists receiving Medicare reimbursements between 2013 and 2019.

Methods: The Centers for Medicare and Medicaid Services Physician and Other Supplier Public Use File was used to determine total reimbursements and number of services submitted by ophthalmologists between 2013 and 2019. Reimbursements were standardized to account for geographic differences in Medicare reimbursement per service. Data from the American Community Survey (ACS) were used to determine socioeconomic characteristics (unemployment, poverty, income, and education) by zip code for the location of each physician's practice. A multivariate linear regression model was used to evaluate differences in annual reimbursements by sex, accounting for calendar year, years of experience, total number of services, ACS zip code data, and proportion of procedural services.

Main outcome measures: Annual Medicare reimbursement and use of billing codes (e.g., outpatient office visits and eye examinations, diagnostic testing, laser treatment, and surgery).

Results: Among 20 281 ophthalmologists who received Medicare reimbursements between 2013 and 2019, 15 451 (76%) were men. The most common billing codes submitted were for outpatient visits and eye examinations (13.8 million charges/year), diagnostic imaging of the retina (5.6 million charges/year), intravitreal injections (2.9 million charges/year), and removal of cataract with insertion of lens (2.4 million charges/year). Compared with men, female ophthalmologists received less in median annual reimbursements (median, $94 734.21 [interquartile range (IQR), $30 944.52-$195 701.70] for women vs. $194 176.90 [IQR, $76 380.76-$355 790.80] for men; P < 0.001) and billed for fewer annual median services (median, 1228 [IQR, 454-2433] vs. 2259 [IQR, 996-4075, respectively]; P < 0.001). After adjustment for covariates, female ophthalmologists billed for 1015 fewer services (95% confidence interval [CI], 1001-1029; P < 0.001) and received $20 209.12 less in reimbursements than men (95% CI, -$21 717.57 to -$18 700.66; P < 0.001).

Conclusions: Female ophthalmologists billed for fewer services and received less in reimbursement from Medicare than men over time and across all categories of billing codes. Disparities persisted after controlling for physician and practice characteristics.