Despite making up over 90 percent of the population, female staff nurses are paid over $5,000 less than their male counterparts, a recent study from the Department of Social and Behavioral Sciences at the University of California at San Francisco shows.

Published in the Journal of the American Medical Association, the comparative study — initiated while lead author Ulrike Muench NUR ’05 GRD ’11, now a professor of nursing at UCSF, was a PhD. student at the Yale School of Nursing — shows that female nurses earn a mean unadjusted total of roughly $10,000 less each year and approximately $155,000 less over a 30-year career than male nurses do.

The study, which controlled for factors such as geographical location, race, seniority and specialty area, could only account for half of the $10,000 raw salary difference between the genders. The cause of the remaining $5,000 pay difference is still unknown. Nurses and academics interviewed expressed concern over what could potentially be systemic gender discrimination.

“I’m a feminist to the core from the ’70s, and I find [these findings] distressing,” said Dean of the School of Nursing Margaret Grey. “You begin to wonder if there is something within the healthcare system where men are more valued than women,” she said, adding that there has been a long history of gender discrimination in healthcare.

Lecturer in nursing Judith Kunisch suggested that the differences in wages may result from women choosing to work in schools and inner city clinics that pay less than do other sites. She added that more women than men work part time and fewer women than men choose to take on executive roles, which may explain the pay differential. However, all of these factors were controlled for in the study.

According to Yale professor of nursing Marjorie Funk NUR ’84 SPH ’92 GRD ’92, salary ranges exist for different clinical levels. As nurses advance through clinical levels, which are numbered one to five, their pay gradually increases.

To examine wage disparities, the study collected nationally representative data spanning the years 1988 to 2008 from the quadrennial National Sample Survey of Registered Nurses. This survey, disseminated both on and offline, provided 87,903 of the registered nurses who were studied. A second data set, the American Community Survey, mapped salaries between 2001 and 2013, providing 205,825 more nurses for the study. Disparities were found in both data sets, with men making up 7 and 10 percent of the two survey populations, respectively.

Muench emphasized that her findings alone cannot confirm gender discrimination in nursing. Rather, she said the study provides nurse employers with the opportunity to examine their pay structures and determine if any pay differences between men and women can be justified.

According to Yale professor of public health and economics Jody Sindelar, a co-author of the study, wage disparities in nursing are particularly interesting because of the abundance of women in the field — only 10 percent of registered nurses in the U.S. are men. Most people would assume that women would be paid just as much as, if not more than, men in nursing, she said.

Erica Zyjewski, a staff nurse at Yale-New Haven Hospital who has been practicing for roughly 10 years, was also surprised by the findings. She noted that though everyone starts at the same base salary, it is uncommon for people to openly discuss how much they make, which she said could explain why these disparities are not widely known.

But Nicole Primoff NUR ’17 said the findings do not surprise her. The pay difference seems to mirror the current trend in all professions to pay men more than women, she said.

Funk agreed.

“Just because nursing is a female-dominated profession does not make it exempt from this sort of thing,” she said.

Funk, who began her career as a staff nurse and returned to this role after completing her PhD., added that a lack of transparency in how much people are paid is a “big problem.”

She supported Zyjewski’s sentiments that wage disparities are hard to identify in real time because of the lack of discussion around salaries.

“I think that’s true of nursing and of many professions. We just don’t know, and we don’t ask,” said Funk. “I think that’s a big problem.”

The study was dedicated to the late Donna Diers NUR ’64, a feminist, mentor to Muench and sixth dean of the School of Nursing. Diers passed away during the early stages of the study.