The negative effects on children’s behaviour of full-time nursery care also act upon their classmates when they start school, research suggests.

For more than 30 years evidence has been building to indicate that preschool children who spend long hours in nursery are more likely to display aggression and disobedience than those who stay at home or attend part-time. Now a new study has found that these effects may be contagious.

Jay Belsky, the director of the Institute for the Study of Children, Families and Social Issues at Birkbeck University, London, who led the study, said: “Being in a classroom with a high proportion of children who have extensive childcare histories affects those with little or no early childcare experience.

“So if your child had no childcare, but ended up in a class where lots of children had childcare, you child ends up being more aggressive. There is a contagious effect,” he said.

The results are a blow to parents who gave up their careers to stay at home with their children in the hope that they would be protected from the negative effects of nursery care.

Professor Belsky and researchers from Temple University in Philadelphia studied a US sample of 3,400 five-year-olds enrolled in 282 kindergarten classes – the equivalent of reception class in Britain.

The children’s parents were interviewed and their teachers completed a questionnaire to measure for each child the frequency of arguing, fighting, getting angry, acting impulsively and disturbing classroom activities.

The children’s competence in reading, maths and general knowledge were combined to give an overall score of academic achievement. These measures were taken in the autumn and again the following spring.

The researchers found that children placed in childcare of any kind, and for longer hours and at earlier ages, displayed significantly more problem behaviour. Those who had spent more time in nursery had better academic scores, although this effect wore off for children in nursery for more than 30 hours a week.

Where there were lots of classmates with childcare experiences, these effects spread to all children in the class. This was the case for the beneficial effects of early nursery care (increased achievement) and the adverse ones (increased problem behaviour). Professor Belsky said that “direct peer contagion” might be responsible for this: “If the only way to survive in class is to push and shove, then all the children will think, ‘Let’s push and shove, too.’ ” It was also possible that teachers were less able to manage whole-class discipline when there was a high proportion of disobedient children in the class. More research was needed, he said, to see whether these effects lasted beyond the reception year.

Beverley Hughes, the Children’s Minister, said that it should not be assumed that findings from the US would apply equally to Britain.

“Evidence from this country suggests that the impact on children of childcare is crucially dependent on quality and the length of time children spend in it,” she said. “We know that when childcare is of high quality and led by well-qualified staff and when children do not spend overly long in it, then the overall benefits are positive.”

She conceded that British evidence suggested a small negative impact on social behaviour for some children from long hours in childcare.

Early learning
The most recent studies to support the Birkbeck findings

June 2007
Preschool children spending most of their day in nursery are more likely to be aggressive and antisocial, according to the National Institute of Child Health and Human Development in the US

April 2007
A report from Oxford University and the Institute for Fiscal Studies concludes that children under three who spend more than 35 hours a week at nursery show higher levels of antisocial behaviour and anxiety

September 2005
Cambridge University and the Free University of Berlin find that children’s stress levels soar in their first days at nursery to 75-100 per cent higher than at home.

Source: Times database

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