A survey of teenage drinking patterns in England has revealed that parents have a strong impact on children's behaviour with alcohol.

Youths are twice as likely to have been drunk several times if they have seen their parents inebriated.

The odds of a teenager having ever had an alcoholic drink are also greater if their parents do not know where they are on a Saturday night, or if they are allowed to watch 18-rated films unsupervised.

The survey of 5,700 schoolchildren found one in four 13-14-year-olds have been drunk more than once, compared to just over half of children (52%) who are 15-16.

The influence of friends is the most significant factor, as the likelihood of youths drinking to excess more than doubles if they spend more than two nights a week socialising. Spending every night with friends multiplies the odds of drinking heavily more than four times.

Claire Turner, from the Joseph Rowntree Foundation, which commissioned the poll, said: "This research shows that parents can have more influence on their teenagers' behaviour than perhaps many assumed. Both what parents say and how they behave have a strong impact on their teenagers drinking, drinking regularly, and drinking to excess."

The report concluded that schools are key to distributing information about drinking.

"The findings suggest that efforts to improve drinking behaviour among young people at a national policy level are best directed at supporting and educating parents," it said.

"This should include positive messages for parents about how they can influence their child's behaviour and stress the importance of parents' own drinking and what their children see and think about this.

"Friends are another key area of influence. Schools could help here by challenging incorrect perceptions about the regularity and scale of heavy drinking by peer groups. Schools could also be a channel for information, getting targeted messages to parents encouraging actions at specific times in their child's development."