Sept. 16, 2008 -- Girls often get a bad rap for gossiping, forming cliques, and other aggressive social behavior, as characterized in the popular movie Mean Girls. Boys, meanwhile, are known for physically aggressive behavior, such as hitting.

A new study, however, says these attitudes may be at least partly unfounded. While boys are indeed more physically aggressive, girls and boys are equally guilty of aggressive social behavior, according to the report published in Child Development.

Researchers did an analysis of 148 studies that included nearly 74,000 children and teenagers. The studies were mostly done in schools and looked both at direct aggression, which is physical or verbal, and indirect aggression, which includes covert behaviors designed to damage another person's social relations with others, without direct confrontation.

"These conclusions challenge the popular misconception that indirect aggression is a female form of aggression," says Noel A. Card, PhD, assistant professor of family studies and human development at the University of Arizona and the study's lead author, in a news release.

Based on the analysis, researchers concluded that often the same kids who are directly aggressive are also indirectly aggressive. Although boys tend to exhibit more direct aggression than girls, there is little difference between girls and boys for indirect aggression. This continues over different ages and ethnicities.

The researchers also note that because of overlap between direct and indirect aggressive acts, it can be difficult to distinguish between the two. The overlap is greater for boys than girls.

They also found consistent links between direct aggression and other adjustment problems. Kids who are directly aggressive are more likely to have problems like delinquency, poor relationships with peers, and low pro-social behavior (which includes things like helping and sharing).

Kids who are indirectly aggressive often have depression and lower self-esteem. However, they tend to have high pro-social behavior, necessary to get support of others such as convincing peers to gossip and exclude others.