NEW YORK — Female physicians at some of the nation’s most prominent public medical schools earn nearly $20,000 less a year on average than their male colleagues, according to an analysis published Monday in JAMA Internal Medicine.
Before adjusting for factors that could influence income, the absolute difference between the genders was more than $51,000 a year, the researchers found.
Several studies have found a persistent pay gap between male and female doctors. But those reports relied mostly on doctors reporting their own incomes, or focused on pay disparities in one specialty or one region, or on starting salaries.
The new study draws on salary information from a much larger, objective sample. The researchers went to great lengths to account for a variety of factors that can influence income, such as the volume of patients seen by a physician and the number of publications he or she had written.
Medical professionals greeted the results with exasperation.
“It’s 2016, and yet in a very methodically strong, large study that covers a broad swath of the country, you’re still seeing at the very least a 10 percent difference in what men and women take home,’’ said Dr. Molly Cooke, a professor of medicine at the University of California, San Francisco, who has studied salary disparities among physicians.
Dr. Vineet M. Arora, an associate professor of medicine at the University of Chicago, wrote an editorial accompanying the study. “This paper is going to make women academic physicians start a conversation with their institutions to promote transparency and gender equality, because at the end of the day, it’s not fair,’’ she said in an interview.
The analysis included data on roughly 10,000 physician faculty members at 24 medical schools. Researchers at Harvard Medical School and Massachusetts General Hospital relied on public databases of employee salaries in 12 states, and data from Doximity, a networking site for physicians, to adjust for factors that can influence income — years since residency, specialty, and age, for instance.
Only public medical schools, not private ones, were included, because states like Florida and Texas post employee salaries online.
After adjusting for a variety of factors, the researchers found that female neurosurgeons, cardiothoracic surgeons, and women in other surgical subspecialities made roughly $44,000 less than comparable men in those fields.
The average pay gap between female and male orthopedic surgeons was nearly $41,000. The difference was about $38,000 among oncologists and blood specialists, about $36,000 among obstetrician-gynecologists, and $34,000 among cardiologists.
Radiology was the only specialty in which women were paid more. Their adjusted average salary exceeded that of male radiologists by roughly $2,000.
The study’s limitations included a lack of information about who was on a tenure track. More important, reported incomes in some states may not include all payments to physicians, but both men and women are likely to have been affected by such an exclusion.
The researchers also found stark variations in the salary gap at different medical schools, suggesting some address pay inequities more aggressively than others.
“The biggest surprise is there are some schools where this doesn’t seem to be an issue,’’ said Dr. Anupam B. Jena, the study’s lead author and an associate professor of health care policy at Harvard Medical School.