Professor Stephen Pilling told Daybreak that children with conduct disorder require a "different way of parenting".
He added that families are not to blame when children are challenging, but parents do need help to get the best out of their child.
More top news
A cervical cancer charity is calling on the public to share smeared lipstick selfies in a campaign to encourage women to have smear tests.
An independent investigation has begun into finances at taxpayer-funded Broadmoor Hospital.
While the economy has shown signs of improving, the number of UK companies issuing profit warnings has hit a six-year high, research shows.