If a pay gap still exists, what are the reasons?
Historically, women and black people in the United States have been paid less than their white, male counterparts.
This gap has been observed across a number of professions, but little research has been done to examine this difference within physicians.
In 2011, the average household income for non-Hispanic whites was $76,063 and, for black people, it was $47,255.
There are an array of reasons for this gap in income, but physicians represent a more homogenous group of individuals. For instance, one reason for the difference in pay between races is education level. For physicians, this factor is removed.
Previous studies investigating racial differences in physicians' pay have been small-scale and reliant on relatively old data. On the other hand, the differences in pay between genders has been more thoroughly investigated.
Race and pay in healthcare
The current study, led by Ruth L. Newhouse, associate professor at Harvard Medical School in Boston, MA, is the first to take a deeper look at the pay differences associated with race among physicians; the team also used the data to assess current gender-based differences in income.
The researchers used data from the 2000-2013 American Community Survey (ACS) and the 2000-2008 Center for Studying Health System Change (HSC) physician survey - both of which include data from across the U.S.
The authors summarize their findings like so:
"We found substantial differences in annual income between black and white male physicians in the U.S., and between male and female physicians overall."
The ACS included data from 43,213 white men, 1,698 black men, 15,164 white women, and 1,252 black women. The HSC used information from 12,843 white male physicians, 518 black male physicians, 3,880 white female physicians, and 342 black female physicians.
The data was adjusted for factors that included specialty, age, hours worked, percentage of revenue from social insurance schemes, and years practicing.
After controlling for potentially confounding variables, the researchers found that white male physicians, as a group, had the highest median income. The ACS survey showed that white male physicians earned $253,042, and black male physicians earned $188,230.
Earlier research has found a difference between the salary of white and black female physicians. However, in the current study, the difference was not as marked as it was between their male counterparts.
White females received a median of $163,234, compared with $152,784 for black females - a less substantial but not insignificant difference. It is also worth noting that females, as a whole, still earned substantially less than the male group.
Why the gap?
The reasons for the pay gap are difficult to understand. Some of the gap could be attributed to black physicians working for Medicaid and Medicare patients more often, where income is likely to be lower. However, when this factor was controlled for, the gap was still seen, so this is not the full answer.
Another potential explanation for the difference might be that black physicians see fewer patients, but when the team adjusted for hours worked, the effect remained.
One reason for the disparity might be a subspecialty split. Although the results were controlled for specialty, subspecialty was not investigated. For instance, cardiologists, on average, might earn more than some specialties and less than others.
However, cardiology itself can be further split into other categories, including preventative cardiology and electrophysiology. It could potentially be that black physicians within each specialty do not have the same opportunities to progress to the highest earning subspecialties.
As with any observational study, conclusions about cause and effect can not be drawn. The researchers argue that sex- and race-based disparities can not be removed by simply opening up opportunities for women and minorities. They say that "efforts to eliminate these disparities might need to look beyond medical school admissions and training to the broader workplace."
The authors close their paper with a call for further studies to achieve a deeper understanding of how these differences develop. It is only by amassing the numbers behind the disparities that change can be brought about.