WASHINGTON, Dec. 30 (UPI) -- Research shows that U.S. Women not only compete differently than men in the workplace, they also compete differently with each other.

"It's been such a taboo subject. To say women have problems with each other is seen as anti-woman, but it's not," said Nan Mooney, author of "I Can't Believe She Did That! Why Women Betray Other Women at Work."

"Women are afraid to raise a problem, so it goes underground, and it comes out in a twisted way. Why is it so hard to work with other women? Why are we so nasty to each other?"

Mooney said women aren't more competitive than men, but that they compete differently -- they often shy from direct conflict for talking behind one another's backs, sabotaging success and feeling threatened by other women, reported USA Today Friday.

However, some researchers say the debate of women competing more passive-aggressively than men is misplaced because employees compete differently based on their personality, not on their sex and the issue perpetuates a negative and untrue stereotype.