Researchers in Queensland analysed 31 studies involving more than 420,000 youth offenders aged between 10 to 19, examining the link between adverse childhood experiences and youth crime.

They found nearly 40 per cent of youth offenders in that age bracket were exposed to more than one bad experience.

“Adverse childhood experiences are potentially traumatic events experienced before a child reaches 18 years of age. These traumatic events consist of household dysfunction and various forms of abuse and neglect,” Wendy Li from James Cook University said.

If children are exposed to maltreatment their likelihood of future criminal activity increased by half, Dr Li said.

More than half of the children analysed experienced domestic violence, nearly half experienced incarceration of a household member and just over 40 per cent had experienced emotional abuse.

Drug or alcohol abuse by family members, parents separating, or a lack of food were present but less prevalent in offenders, the data showed.

The influence of more than one adverse childhood experience paints an even bleaker picture with a near 100 per cent increase in youth reoffending if exposed.

A safe, positive home environment as well as strong social bonds lowered youth recidivism, researchers found.

But child welfare placement, emotional and behavioural problems, drug use, mental health problems and negative emotionality made things worse.

“As far as we know there has been no other systematic review of the mechanisms underlying the relationships between adverse childhood experiences and youth recidivism,” Dr Li said.

“This new work could help service providers to further focus their assistance to youth.

“A wide range of evidence-based prevention and intervention strategies to strengthen the protective factors and weaken the risk factors would also be useful.”