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Aggressive 5 year olds nearly five times more likely to be aggressive 14 year olds

Media Release

28 May 2001

A new report released today by the Australian Institute of Criminology reveals that aggression in a child's preschool years is a powerful predictor of aggressive and delinquent adolescent behaviour.

Aggression and the Development of Delinquent Behaviour in Children, by W. Bor, J.M. Najman, M. O'Callaghan, G.M. Williams and K. Anstey, reports on some very important findings of the Mater University Study of Pregnancy (MUSP).

The report analysed data provided by mothers for almost 3800 children at age five and again at 14 years of age.

"While there are a number of other significant variables - such as gender, poverty and divorce - aggression at age five is the strongest predictor of adolescent delinquency", Dr Adam Graycar, Director of the Australian Institute of Criminology said today.

"This report shows that if aggressive behavioural problems develop in preschool years, a significant proportion of those children will continue to experience similar problems in adolescence. That's why effective early intervention programs can be among the most productive crime prevention strategies", Dr Graycar said.

More than 31 per cent of those children classified as aggressive by their mothers at age five were still classified as aggressive at 14 years of age

In comparison, only 6.3 per cent of those children classified as non-aggressive at age five were classified as aggressive at 14 years of age.

And 48 per cent of those 14 year olds classified as aggressive were also classified delinquent, while only 3.5 per cent of those classified as non-aggressive were classified delinquent.

Increasing juvenile crime is a source of concern to the Australian community, with an estimated one-third of all crime perpetuated by juveniles at an estimated cost of $1.5 billion per year.

Repeat offenders who often have a past history of sustained aggressive behaviour carry out a significant proportion of juvenile crime.