Female surgeons in Ontario earn 24 per cent less than their male counterparts for each hour they spend operating, according to a new study.

The study, published in the journal JAMA Surgery on Wednesday, found these disparities exist even in a fee-for-service system, which is considered less gender-biased than salary-based systems. Despite this, women in all specialty areas are more likely to do procedures that pay less, the researchers found.

Within general surgery, for example, women performed more operations such as cyst removal and biopsies, while their male counterparts did more lucrative procedures such as gastric bypasses, said one of the authors, Fahima Dossa, a surgical resident at the University of Toronto.

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Dr. Dossa suggest one reason may be that women choose or are pushed into less lucrative specialties, and less lucrative procedures within specialties. She also said female surgeons likely get fewer referrals over all than their male counterparts, and those they do get tend to be on the lower-paying end.

“It looks like women are having fewer opportunities to do the more higher-paying procedures,” Dr. Dossa said in an interview. “There’s often this [view] that women are choosing these things. Women are choosing these specialties, and choosing to do certain types of procedures. But I can assure you women are not choosing consciously to make less money.”

Nancy Baxter, a general surgeon at St. Michael’s Hospital in Toronto and an author of the study, said female surgeons may also be less aggressive when it comes to billing.

“A lot of time, [the gender gap] gets attributed to the women; so the women aren’t working hard enough, the women aren’t choosing the right specialties,” Dr. Baxter said. “What you see here is it’s not the women, it’s the system. So if the system is giving to women procedures that are worth less per hour, we have to fix the system.”

The research team, led by St. Michael’s Hospital, compared the earnings of female and male surgeons using data from the non-profit research institute ICES, formerly known as the Institute for Clinical Evaluative Sciences. It looked at more than 1.5 million elective surgical procedures performed on adult patients by 3,275 surgeons in Ontario in eight specialties between January, 2014, and December, 2016.

Based on the amount paid for the procedures and the time it takes to do them, the researchers found over all that male surgeons earned $300.86 an hour on average, compared with $214.59 an hour for female surgeons. When they compared female surgeons with their male counterparts within each specialty, they found male surgeons earned $24.63 more an hour in general surgery, $73.73 more an hour in orthopedic surgery, and $79.39 more an hour in cardiothoracic surgery. In gynecology, even though female surgeons outnumber males, male surgeons earned $22.92 more an hour.

In almost all cases, female and male surgeons took the same amount of time to perform identical procedures, so the researchers noted the differences cannot be explained by women taking longer.

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The researchers suggested one reason: Female surgeons may have less aggressive billing behaviours. In other words, Dr. Baxter explained, some procedures can be billed in different ways and some doctors may choose the way that pays the most, or add on a procedure, even though it may not be appropriate.

Dr. Baxter also said even though physicians are not supposed to turn down referrals for patients who require less lucrative procedures, those who do so can earn more money. She said she suspected this may be one reasons female surgeons end up with procedures that do not pay as well.

Additionally, the researchers found that women were most highly represented in specialties with the lowest earnings, such as gynecology. Of the 819 female surgeons they studied, 400, or nearly 49 per cent, practised gynecology. They suggested this may, in part, be because female trainees are discouraged from certain disciplines.

Clover Hemans, president of the Federation of Medical Women of Canada, who was not involved in the study, said the findings add to the evidence of gender-based pay inequities in medicine.

“This study certainly comes as no surprise to me,” said Dr. Hemans, who is a family physician in Oakville, Ont.

She said female surgeons tend to receive referrals for patients who have additional issues, such as anxiety, and do not get remunerated for taking the time to address these needs.

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“There’s a dual expectation there that you will manage that [patient’s anxiety], and you don’t get paid any more to do that,” she said.

In a statement from the Ontario Medical Association, president Sohail Gandhi said his organization, which represents Ontario physicians, believes in equal pay for equal work. He said the reasons for gender-based inequities are not well understood.

“[M]ore research is needed so we can make an 'apples-to-apples’ comparison between male and female billings and identify the factors that are driving earnings differences,” Dr. Gandhi said, noting the OMA began researching the issue this year. “Once we have a clear understanding of the causes and how they interrelate, we can take steps to address this problem and narrow the gap.”

Dr. Baxter said one measure that could help would be a pay structure that groups surgeons who perform similar work together, and referrals are pooled and given to them in an unbiased fashion. In this way, every surgeon would do the same number of gastric bypasses, for instance, and the same number of biopsies and cyst removals.

“It’s time to stop trying to fix women or blame women,” she said. “We have to do something to create solutions, or else in another 30 years, we’ll be having the same discussion.”

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