Researchers in the US have identified six risk factors that help predict the likelihood of a child bullying others.

These factors are media violence exposure, bias toward hostility, low parental involvement, gender (boys were more likely to bully than girls), physical victimisation, and prior physical fights.

The researchers profiled 430 children in Minnesota between the ages of 7 and 11, and found that those with the most risk factors were most likely to be violent.