Bullies are more likely to come from violent homes
Research on bullying published by the young people's charity Young Voice claims that parenting styles can influence whether children will become the victims and perpetrators of bullying.
"Children need to learn to fight their own corner - and if children are deprived of the experience of fighting back in the safety of their own home, it can make them more likely to become victims," said the charity's executive director, Adrienne Katz.
Parenting styles can also influence the likelihood of children becoming bullies, says the survey.
It found that bullies were more likely to come from families in which parents did not treat their children equally and bullies were more likely to have little respect for their parents.
Both bullies and their victims were more likely to come from homes in which corporal punishment was used and where other more aggressive violence took place.
Knives and baseball bats
According to the survey, 42% of severely bullied boys and a third of bullies had been victims of violence at home. This included 35% of severely bullied boys who said they had been "beaten" at home.
Among girls who were bullies, 28% reported that they had experience of violence at home.
The report also found that bullies were finding new ways of intimidating their victims, such as using threatening text messages on mobile phones.
The research, which draws on three surveys and a series of one-to-one interviews between 1996 and 2000, also claims that there are weaknesses in how schools tackle bullying.
While schools are required to have anti-bullying policies, the survey claimed that only half of teenagers knew that such policies existed.
Such low awareness among pupils suggested that there were bullying problems "on the ground" which were not being tackled by school policy makers.
Researchers also found that although bullying was not becoming more widespread, it was becoming more violent, with attacks escalating to using knives and cricket and baseball bats.