Douglas Gentile, Muniba Saleem and Craig Anderson of the Center for the Study of Violence at Iowa State University analyzed 14 scientifically documented effects on children's physiological and psychological well-being, both in the short- and long-term.

Media violence effects "are likely to become greater over time, as different media converge, become more interactive, become more global, and colonize more spaces in our lives," the authors said in a statement.

More than half of American parents believe violence makes children more aggressive, yet only a small percentage establish rules regarding content for their households, the researchers said.

The findings are published in the Social Issues and Policy Review.