They found that children of parents who took part in a parenting programme developed in the US showed improvements in aggression and self-control.
Because these are risk factors for the development of antisocial behaviour and mental health problems in later life, they suggested similar evidence-based programmes should be adopted under government-funded schemes such as Sure Start.
The study included 153 parents from socially disadvantaged areas in north and mid-Wales with preschool children at risk of developing conduct disorder.
The parents were then divided so 49 were put on a waiting list, while 104 were assigned a place on the Webster-Stratton Incredible Years basic parenting programme.
This programme, designed by a US psychologist, is designed to help parents learn to set limits for their children, increase good behaviour with praise and be consistent in using gentle punishment for bad behaviour.
Parents attending the programme had 12 weekly two-hour sessions in groups of between six and 12.
The researchers reassessed the children six months later and found that children whose parents were assigned to the programme were rated as having fewer behavioural problems than those whose parents were put on the waiting list. They were also less hyperactive and had more self-control.
In addition, parents who had taken part in the programme suffered less stress and depression than parents put on the waiting list.
Lead researcher Dr Judy Hutchings, research director at the School of Psychology at the University of Wales, Bangor, said that this showed how Sure Start programmes could be improved.
‘The government gave money to Sure Start services but did not tell them what to do,’ she said. ‘We used an evidence based programme and provided everything to ensure that it was delivered properly, and we found it produced a statistically significant improvement in the children’s behaviour.’