Study leader Dr. Rashmi Shetgiri of the University of Texas Southwestern Medical Center and Children's Medical Center in Dallas examined the prevalence of bullying reported by parents who took part in the National Survey of Children's Health from 2003 to 2007.
Nearly one in six youths ages10-17 bullied others frequently in 2007 and 23 percent of children had bullied another youngster in 2003 compared to 35 percent in 2007.
Factors that increased the likelihood that a child bullied included that their parents frequently felt angry with them or felt their child bothered them a lot; children had an emotional, developmental or behavioral problem; and mothers reported less than very good mental health.
In addition, one in five bullies has an emotional, developmental or behavioral problem, more than three times the rate in non-bullies, Shetgiri notes.
However, parents who share ideas and talk with their children, and who have met most or all of their child's friends are less likely to have children who bully, Shetgiri finds.
"Parents can find effective ways to manage any feelings of anger toward their child and can work with healthcare providers to make sure any emotional or behavioral concerns they have about their child, as well as their own mental health, are addressed," Shetgiri says.
The findings were presented at the Pediatric Academic Societies annual meeting in Denver.