Adolescent bullies, victims and bully-victims (defined as those who are simultaneously both bullies and victims) were more likely to carry weapons.

Previous research suggests adolescents involved in bullying are more likely to carry weapons than peers who are not involved in bullying.

The authors reviewed and analyzed 22 studies for (n=257,179), 15 studies for (n=236,145) and eight studies for bully-victims (n=199,563).

Studies indicate that bullies, victims and bully-victims were more likely to carry weapons. Studies conducted in the U.S. found stronger associations between being a bully-victim and weapon-carrying than studies in other countries.

"The current meta-analysis suggests that bullying is related to weapon carrying among adolescents and further establishes bullying as a risk factor for adolescent problem behavior. Given the wide range of negative implications bullying may have, it is important that schools endeavor to reduce bullying among their students, preferably by using evidence-based methods." Mitch van Geel, Ph.D., of Leiden University, the Netherlands, and colleagues wrote in their JAMA Pediatrics paper.

More information: JAMA Pediatr. Published online June 9, 2014. DOI: 10.1001/jamapediatrics.2014.213