By Paula Dear BBC News website

Not all children are upset by their experiences, says one campaigner

Under-16s frequently become victims of crime in the UK - but it is difficult to know exactly how many are affected.

A baffling array of surveys and studies are conducted, offering different conclusions and often employing incomparable methods.

Some campaigners say the research is patchy and more coherent data is needed.

But others urge caution on the subject, saying there is increasing over-reaction in society to the low-level crime and anti-social behaviour children have always experienced "as part of growing up".

An inescapable fact is under-16s are not interviewed in the annual government surveys that are combined with police statistics to provide a picture of crime and victimisation in the UK.

This, combined with a tendency in many children not to report crime, makes it difficult to determine exactly how many are victims and the effect it has on them.

We didn't think we should get the police involved - it would have just been a big hassle Sonal, 14 'They rob you for anything'

Three separate crime surveys are conducted for England and Wales, Scotland and Northern Ireland.

In the British Crime Survey (BCS), for England and Wales, 40,000 over-16s are interviewed every year about their experiences of crimes - including those not reported to the police.

The Home Office said under-16s were excluded from the BCS for "methodological reasons", including the need to design questions differently for younger respondents.

But this year, for the first time, the department published a separate Crime and Justice Survey (CJS) that included interviews with 10- to 15-year-olds.

Conducted in 2003, it found 35% of 10- to 15-year-olds had been victims of at least one "personal" crime - assault, robbery or theft.

This proportion is similar among 16- to 25-year-olds - but 21% higher than that among the over-25s.

About one out of every five under-16s had been assaulted, and three out of every five who had experienced violence in the previous year had done so more than once.

There could be a little less youth offending if more resources were given to helping young people who are victimised Victim Support head of research and development Peter Dunn

But a MORI Youth Survey of 11- to 16-year-olds attending school 2004 found the prevalence of assaults to be far lower - 13%.

MORI also found 49% of mainstream school pupils and 55% of excluded pupils had been victims of crime.

It found little difference in the amount of victimisation between racial groups, although the types of crime experienced differed.

But other research contradicts this, indicating children from ethnic minorities are more at risk of crime.

A 2002 Crimestoppers survey found 18% of under-15s had been victims of crime - but more than half of them failed to report it to police.

Of 403 young people interviewed by the 2000 Scottish Crime Survey, half said they had been victims of bullying, theft, harassment, violence or sexual crime.

WHO FOUND WHAT? MORI, 2004: 49% of mainstream school pupils had been victims of crime Howard League for Penal Reform, 2004: 95% of more than 500 Northamptonshire primary school children surveyed said they had been victims of any type of crime Crime and Justice Survey, 2003: 35% of 10- to 15-year-olds had been victims of personal crimes Victim Support, 2003: 25% of 12-16s had a crime committed against them in the last year Crimestoppers, 2002: 18% of under 15s were victims British Crime Survey,1992: Only BCS survey to include under-16s found 66.6% had been victim of crime

And in a 2004 survey, 95% of more than 500 Northamptonshire primary school children told the Howard League for Penal Reform they had experienced crime, including house robberies.

Children who had offended were more likely to also be victims and vice versa, said the Crime and Justice Survey - a finding backed by other research.

The cause for the link "would only be apparent over time", it said.

These links "ought to be taken more seriously," said Peter Dunn, head of research and development for Victim Support, which provides support and information to children who are victims of crime, and their parents.

A "lack of coherent" research on the subject was a real issue, he added.

Mr Dunn said young people were more likely to be repeat victims and less likely to report incidents to the police than adults were.

"There could be a little less youth offending if more resources were given to helping young people who are victimised'', he added.

Children are the same as they have always been - low-level anti-social behaviour towards each other is part of the process of growing up Frances Crook, Howard League for Penal Reform

But Frances Crook, director of the Howard League for Penal Reform - which runs two-day crime and citizenship seminars for schoolchildren - said young people had not really changed over the generations.

The charity lobbies for better crime prevention for children - but Ms Crook said society had to be "careful" about over-reacting.

"Children are the same as they have always been - low-level anti-social behaviour towards each other is part of the process of growing up."

"What we call a crime has changed, and our tolerance levels have changed."

Ms Crook said it was "impossible" to determine how many "victims" there were.

Mobile phones are often targeted

The situation was clearer with more serious crimes but it was the "low-level stuff that the kids are generally not that upset about", she added.

Ms Crook is "wary" of the government's Crime and Justice Survey.

"You have to work much more intensively with children.

"Our survey is done after two full days of discussion, and even then it is only an indicator.

"It is important the issue is handled sensitively and consistently.

"Sometimes there are disproportionate responses to something quite minor.

"We overreact to anti-social behaviour."