Bullying and weapon carrying: a meta-analysis

JAMA Pediatr. 2014 Aug;168(8):714-20. doi: 10.1001/jamapediatrics.2014.213.


Importance: Studies suggest that adolescents involved in bullying are more likely to carry weapons than their uninvolved peers.

Objective: To use meta-analyses to determine whether victims, bullies, and bully-victims are more likely to carry weapons than uninvolved peers.

Data sources: PsycINFO, ERIC, MEDLINE, LILACS, EMBASE, and Dissertation Abstracts International were searched for relevant publications (1950 through January 2014). The reference list of a review article and reference lists of retrieved articles were checked for further relevant studies.

Study selection: Studies were included if they provided an effect size comparing the weapon carrying of adolescent victims, bullies, or bully-victims with that of uninvolved peers. Studies that included individuals older than 21 years were excluded, as were studies that focused on incarcerated youth or youth diagnosed as having a psychopathologic condition.

Data extraction and synthesis: Studies were coded independently by 2 of us. The agreement rate was 93%. Effect sizes were coded that compared victims, bullies, or bully-victims with uninvolved peers. Meta-analyses were based on 22 studies for victims (n = 257 179), 15 studies for bullies (n = 236 145), and 8 studies for bully-victims (n = 199 563).

Main outcomes and measures: This study focused on weapon carrying among adolescents. Hypotheses were formulated before the study.

Results: Victims (odds ratio, 1.97; 95% CI, 1.62-2.39), bullies (3.25; 2.72-3.89), and bully-victims (4.95; 3.77-6.50) were more likely to carry weapons than uninvolved peers. Analyses provided no indication of publication bias. Studies conducted in the United States found stronger relations between being a bully-victim and weapon carrying (odds ratio, 7.84; 95% CI, 6.02-10.21) than studies from other countries (3.62; 2.30-5.68; Q1 = 8.401; P = .004).

Conclusions and relevance: Involvement in bullying as a victim, bully, or bully-victim is related to weapon carrying.

Publication types

  • Meta-Analysis
  • Review

MeSH terms

  • Adolescent
  • Bullying / psychology*
  • Humans
  • Risk Factors
  • Weapons*