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Lost opportunities for intervention: undetected markers for the development of serious juvenile delinquency.

INTRODUCTION
Persistent serious delinquency in young males rarely starts without a history of problem behaviour in childhood. This paper addresses the following questions: (1) At what age does persistent serious offending emerge for the first time? (2) What proportion of persistent serious delinquent boys qualifies for a diagnosis of a disruptive behaviour disorder? (3) What proportion of persistent serious delinquent boys receive help for their behavioural or educational problems, either from mental health professionals or from personnel at school?


METHOD
Eight waves of assessments from the oldest sample (ages 13 to 18.5) of the Pittsburgh Youth Study were used to classify boys as persistent serious violent offenders, persistent serious property offenders, persistent non-serious offenders, and non-offenders based on their self-reports. Juvenile court records, diagnostic information and information about help for mental health problems were used.


RESULTS
Almost half of the boys who eventually become a persistent serious offender already have an onset of their serious delinquent behaviour by age 12. Two-thirds of the boys who come to the attention of the juvenile court already had behaviour problems for at least five years, and one-third were diagnosed as having a disruptive behaviour disorder by age 13. However, less than half of the persistent serious delinquents had received any help from either mental health professionals or from personnel in schools.


CONCLUSIONS
Early behaviour problems and a diagnosis of disruptive behaviour disorder constitute targets for intervention. The relatively low rate of interventions for boys with these problems and who later become persistent serious offenders indicates a high under-utilization of opportunities to prevent serious delinquency by parents and professionals.