Thousands of children entering primary school this year will be better prepared to learn as a result of the Sure Start programme, according to an official evaluation.
The findings are in contrast to an earlier study, which found that some of the most disadvantaged families - such as teen and lone parents - did less well in areas served by the government scheme.
The study of 9,000 families reveals that three-year-olds in areas with a Sure Start centre are more likely to be helpful, kind, generally obedient and independent. Parenting was found to be better in these areas too, and children were more likely to be read to, taught songs and have the chance to paint and draw at home. Mothers also said they received more support.
Bernadette Duffy, head of one of the first Sure Start children's centres, Thomas Coram near King's Cross, London, said: "We have noticed that children coming into the nursery aged three have better dispositions for learning, they are more confident, their language skills are more developed, and they know to put an apron on before playing with sand and water."
The centres provide early education and child care for three and four-year-olds, drop-in sessions for children, support for childminders, family health services, special needs support, outreach for parents and a link to Jobcentre Plus.
Since 2003, the service has been introduced in other areas and the aim is to open 3,500 Sure Start children's centres by 2010.
The study, led by Ted Melhuish, professor of human development at Birkbeck College, London, looked at the impact of Sure Start programmes running in 524 of the most disadvantaged areas. He examined 14 indicators, ranging from children's behaviour to whether mothers smoked, and found improvements in seven of these areas.
Beverley Hughes, children's minister, said: "There are some middle-class families using the centres, and that's great. We need to make sure that people who need these services the most are getting the benefit, but it is a universal service."
The study found only one adverse effect of the programme - that black Caribbean children in Sure Start areas were less likely to show positive social behaviour than their peers in non-Sure Start areas. Professor Melhuish said this finding was likely to be due to chance.
The difference in results between the two studies is believed to be down to children participating in Sure Start programmes for longer and improvements in the service.
Tracey Daniel, head of the Carlinghow and Wilton children's centre in West Yorkshire, said: "There has been a settling-in period. Parents and the general public didn't know what we were for, or saw us as part of the school system. Now health services have come on board and are promoting us through health visitors and midwives."