), finds that primary pupils are far more likely to empathise with a victim of bullying than older pupils.
"Young children are much more focused on `It's not kind'," Dr Palmer says. "Adolescents are more likely to think that it's none of their business. It's not that older children can't empathise. But there's so much else going on for them that they have to weigh it all up."
Teenagers, for example, are more likely than younger children to worry that, by intervening, they will set themselves up as potential victims. This can lead them to dismiss verbal bullying as "not a big deal" or "something that happens all the time".
Sue Minto, head of ChildLine, understands this reaction. "Young children don't have the same sort of immediate ability to think through what the implications are for them," she says. "They just think: `That's not OK.'
"With older children, you have a level of experience and your thinking processes are probably quicker."
The exception is when teenagers feel a strong sense of identification with the victim. It is not enough, however, that the victim and the bystander share something - the common factor must also be meaningful to the bystander.
"If you're a Muslim and the victim is Muslim, and being Muslim is a particularly strong part of your identity, then you're more likely to help a person who's a Muslim," Dr Palmer says. "For adolescents, the standard response is, `Well, it's nothing to do with me.' But if they do have that group affiliation, then they feel that it's something to do with them and it's worth their time."
Ms Minto insists that adults should not judge teenagers for this. "We can say that it's worrying, concerning, surprising," she says. "But there's a tendency for all of us not to put our own head above the parapet in case we're the next target. Bullies can be intimidating."
Dr Palmer believes that her findings can be used effectively by schools in developing anti-bullying strategies. She recommends addressing teenagers' default response of "It's no big deal".
"Try to promote the understanding that it is a big deal for the kid who's experiencing it," she says.
This sentiment is echoed by David Castles, principal of Heyford Park Free School in Oxfordshire, which teaches 4- to 19-year-olds. All pupils have weekly circle-time sessions, whatever their age group. "We try and promote a really strong all-through ethos, where every child sees themselves as part of a small community," he says.
But peer-group behaviour is also significant: teenagers who see their classmates intervening to stop bullies are more likely to say that they would intervene themselves.
"Group-based bullying taps into wider issues of prejudice and discrimination," Dr Palmer says. "Strategies to tackle prejudice are helpful. But also, if we can promote a stronger sense of community at school - if they all have a common sense of identity - then the kids will benefit as well."
`Strong sense of common identity'
David Castles, principal of Heyford Park Free School in Oxfordshire, which teaches four- to 19-year-olds, believes he has worked out how to ensure that pupils of all ages are willing to combat bullying.
Creating a strong sense of community within a school can mean that pupils feel obliged to intervene when they see bullying, Mr Castles says.
"I think it's about harnessing that sense of shared responsibility that children in primary schools have," he adds. "Often, in secondary schools you introduce a pecking order where adolescents feel much more self-conscious about standing up and speaking out.
"We're a relatively small school, so children have a strong sense of common identity. We're trying to create an environment where every child feels confident enough to do the right thing. What we really want is to harness that sense of idealism that younger children have, and make sure they carry it through."