How important are you at work? According to a new study, men tend to exaggerate their importance at work while women — you guessed it — do the exact opposite.

The study, conducted by researchers from Harvard Business School and the Wharton School at the University of Pennsylvania, sought to determine whether men or women were more likely to assess their own work positively.

To do the study, researchers conducted an experiment where 900 workers were asked to take a 20-question test from the Armed Services Vocational Aptitude Battery, an exam used to determine whether someone is qualified to enlist in the U.S. Armed Forces, Marketwatch reported. Participants were then asked to rate on a scale of 0 to 100, with 100 being the best, how well they thought they did on the test and to rate their overall performance in different ways.

The research discovered that when individuals are asked to rate their performance — in job applications, job interviews, performance reviews and a wide range of other environments — women consistently rate their performance less favorably than equally performing men. Specifically, women on average reported their performance as being 15 points lower on the 100-point scale than the average man.

In fact, even after some of the participants were told how well they scored on the test and how that compared with others’ scores, some women still assessed themselves more poorly than men.

Researchers said an explanation for their findings could be that women believe that self-promotion is an inappropriate way to behave or that they are afraid of the possibility of backlash over being boastful about their abilities.

Read the full study online.