Trends in the Earnings of Male and Female Health Care Professionals in the United States, 1987 to 2010

Nearly 40 years after the adoption of the Title IX Amendments of the US Civil Rights Act, women account for almost 50% of US medical students and more than one-third of all physicians. Historically, female physicians have earned considerably less than male physicians, though in the 1990s much of this was attributable to gender differences in specialty choice and hours worked.¹ However, more recent data suggest that female physicians currently earn less than male physicians even after adjustment for specialty, practice type, and hours worked.² Salary differences between men and women currently exist among physician researchers as well.³ This raises questions about whether the gender gap in earnings among US physicians has closed over time, particularly compared with the earnings gap for other health care professionals and workers overall. Comparing earnings of male and female physicians over time is important in assessing the impact of policies to promote gender equality among physicians.

Using nationally representative data from the March Current Population Survey (CPS) from 1987 to 2010, we estimated trends in the male-female earnings gap among physicians, other health care workers, and workers overall. The CPS has been used to study trends in physician work hours and earnings.^4,5 The CPS data are collected monthly and are based on personal and telephone interviews of approximately 60 000 households. The data are deidentified and made publicly available, and thus this study was exempt from institutional board review.

We used self-reported data from the CPS on occupation, hours worked, annual earnings, age, sex, and race. Response rates exceeded 90% across years.⁵ Physicians were identified based on a self-reported occupation of physician or surgeon. Other health care professionals were identified based on a self-reported occupation of dentist, pharmacist, nurse, physician assistant, or health care and insurance executive. Because the values of earnings reported were capped by the US census to protect identities (eg, the cap was $250 000 in 2010), we analyzed trends in median annual earnings. We analyzed 3 periods (1987-1990, 1996-2000, and 2006-2010) to smooth annual fluctuations in the data. We excluded individuals younger than 35 years to focus on physicians completing residency.⁶ The CPS does not collect data on physician specialty. Additional limitations of the CPS for studying physician earnings have been noted elsewhere.⁵

We used median regression analysis to study trends in earnings across occupations, adjusting for age, sex, race, hours worked, and state. We adjusted for hours worked to avoid overstating gender differences in earnings if female physicians work fewer hours. For each occupation, we estimated a pooled regression model of both women and men, with interaction terms between sex and year to estimate sex-specific trends. We predicted earnings holding covariates other than sex and year fixed at their mean values. Dollar values were normalized to 2010 dollars.

Our sample included 1 334 894 individuals, including 6258 physicians and 31 857 other health care professionals. The percentage of physicians surveyed who were female increased from 10.3% in 1987-1990 to 28.4% in 2006-2010, consistent with prior reports.⁷ Men accounted for a majority of workers in other health care occupations except for registered nurses and physicians assistants.

Adjusted earnings of male physicians in 1987-1990 exceeded those of female physicians by $33 840 (20.0%) (Table). There was no statistically significant improvement over time in the earnings of female physicians relative to male physicians. The physician earnings gender gap was $34 620 (16.3%) in 1996-2000 (P = .65, compared with 1987-1990) and was $56 019 (25.3%) in 2006-2010 (P = .46, compared with 1987-1990). Overall, the gender gap fell considerably outside of the health care industry but inconsistently within it. The gender earnings gap for registered nurses and pharmacists was smaller than for physicians and workers overall, and it fell over time. For dentists, physician assistants, and health care executives, the gender gap was greater than for workers in a non–health care occupation and fell consistently only for health care executives.

A gap in earnings between male and female US physicians has persisted over the last 20 years. Although we adjusted for differences in hours worked and years of experience, our study was limited because the CPS does not include data on specialty, practice type, procedural volume, and insurance mix, all of which could influence our findings. Our inability to adjust for these factors likely explains why we found a gender gap in earnings in 1987-1990, while a previous analysis in this period that adjusted for these factors did not.¹ Recent studies suggest, however, that gender differences in earnings still exist even after adjustment for these factors.²

While it is important to study gender differences in earnings after accounting for factors such as specialty choice and practice type, it is equally important to understand overall unadjusted gender differences in earnings. This is because specialty and practice choices may be due to not only preferences of female physicians but also unequal opportunities. For example, are unadjusted earnings differences between male and female physicians due to a preference of female physicians for lower-paying specialties (eg, pediatrics or primary care) or do female physicians have less opportunity to enter higher paying specialties despite having similar preferences as male physicians? The etiology of the persistent gender gap in physician earnings is unknown and merits further consideration.

Corresponding Author: Anupam B. Jena, MD, PhD, Department of Health Care Policy, Harvard Medical School, 180 Longwood Ave, Boston, MA 02115 (jena@hcp.med.harvard.edu).

Published Online: September 2, 2013. doi:10.1001/jamainternmed.2013.8519.

Author Contributions: Study concept and design: Seabury, Chandra, Jena.

Acquisition of data: Seabury.

Analysis and interpretation of data: Seabury, Chandra, Jena.

Drafting of the manuscript: Seabury, Chandra, Jena.

Critical revision of the manuscript for important intellectual content: Seabury, Chandra, Jena.

Statistical analysis: Seabury, Chandra.

Study supervision: Seabury, Jena.

Conflict of Interest Disclosures: None reported.

Funding/Support: Dr Chandra was supported by grant P01 AG19783-02 from the National Institute of Aging.

Role of the Sponsor: The design, conduct, analysis, interpretation, and presentation of the data are the responsibility of the investigators, with no involvement from the funding sources.