A doctor often gets called "Doctor" as a show of respect in public and among colleagues — well, at least when he is a man.

A woman is a different matter, according to Mayo Clinic research, which found gender bias among the nation's most highly trained professionals.

Dr. Julia Files, a Mayo internist, recalled the end of a recent presentation she gave with three male colleagues.

"What a lovely afternoon," the moderator told the crowd. "Let's thank Doctor X, Doctor Y, Doctor Z — and Julia — for an excellent presentation."

After hearing similar stories, Files and colleagues decided to test the theory of gender bias by reviewing videotapes of 321 introductions that occurred during 124 internal medicine grand rounds lectures at Mayo campuses in Rochester, Minn., and Scottsdale, Ariz. (Grand rounds are weekly conferences to review tough cases or medical trends.)

And while female introducers identified male speakers with the title of doctor 95 percent of the time, male introducers only did the same for their female colleagues 49 percent of the time. Male doctors were less formal, in general, but still referred to male colleagues as doctors 72 percent of the time.

"Men are part of the 'in' group in medicine," Files said, "and so there is less formality because of their peers belonging to the 'in' group."

The research examined introductions of speakers who had medical degrees, pharmacy degrees, doctorates or medical dentistry degrees. Only once in 46 introductions did a female fail to introduce a female speaker by the title of doctor, according to the study, which was published online last month by the Journal of Women's Health.

Doctors might shrug off these slights, which introducers probably don't intend, the study noted, but the "failure to use a woman's professional title is a subtle reinforcement that women are of lower status and may be one of the factors contributing to the consistent finding that female physicians are paid less than their male counterparts, are less likely to be appointed to leadership positions, and are more likely to pursue career tracks with historically fewer opportunities for academic promotion."

No funding was acquired for the study; researchers volunteered to watch videos and analyze results on their own.

A limitation was the lack of knowledge of whether introducers in the videos had personal relationships with speakers that affected their formality. But the research group took steps, Files said, including the use male and female video reviewers, to ensure the reliability of the results.

Jeremy Olson • 612-673-7744