If you have a gun during a fight, think twice about the protection it might offer.

Epidemiologists at the University of Pennsylvania School of Medicine yesterday announced the findings of a study about whether guns are protective or perilous during an assault.

It found that those possessing a gun in an assault situation were 4 1/2 times more likely to be shot than those not possessing one, according to the study's author, Charles C. Branas, associate professor of epidemiology.

It was released online this month in the American Journal of Public Health and will be printed in the November issue.

"It's a big question that has been asked for years," Branas said of the reason behind the study.

"One that is a very U.S.-oriented question but that also has applications outside the U.S.," Branas said.

Branas said that along with a team of about a dozen people, including colleagues, members of the Philadelphia Police Department and the city Medical Examiner's Office, he conducted a case control study, or an approximation of an experiment.

From 2003 to 2006, the police notified Branas and his team about all shootings that occurred in the city, he said.

"We would then get the data and pass it along to a survey-research firm to find an individual who had not been shot and ask them what they were doing and where they were at the time of the shooting," Branas said.

On average, they found that guns did not protect those who possessed them from being shot in an assault, he said.

"This study was an excellent way to approximate this experiment and begin to get an idea of how it works," Branas said.

He and his team hypothesized reasons as to why guns didn't protect individuals from being shot in an assault, including feeling falsely empowered and overreacting, possibly instigating something with someone, or entering a dangerous situation that one might normally avoid.

"I don't think this study is the end," Branas said. "I think it should help begin to raise awareness about gun possession and begin to question whether an individual is absolutely safe in possession of a firearm or whether it's promoting a false sense of security."