Children raised in marital homes are better behaved than those brought up by unmarried parents, according to major research funded by the Department for Education.
The study of around 3,000 children aged three to 16 found that those with married parents showed lower levels of anti-social attitudes and hyperactivity.
They were also more confident, kind and responsible, according to the research from the University of Oxford and the University of London.
The study, launched in 1997, tracked the long-term impact of factors such as financial income, social class and marital status on exam grades and behaviour.
It covered a child’s self-regulation, which includes traits such as showing leadership, confidence and taking responsibility, alongside pro-social behaviour, anti-social behaviour, and hyperactivity.
The study said: “The marital status of parents in the early years, when children were first recruited to the study, was also a significant predictor of changes in self-regulation and pro-social behaviour during secondary education.
“Single parent status also predicted increases in hyperactivity in adolescence and anti-social behaviour. Students in lone parent families showed small but statistically significant increases in both negative behaviours and decreases in both positive behaviours.
“In addition, students of parents who were living with their partner but unmarried in the early years were found to show small decreases in self-regulation and pro-social behaviour and an increase in hyperactivity.”
Professor Edward Melhuish, an academic who carried out the research, commented that the “extra support from living in a stable marital home tends to lead to a better environment over the long term for the child”.
A recent US study showed that the negative impact of divorce on children is the same whether parents remain amicable or not.
Researchers asked 270 parents who were divorced or separated between 1998 and 2004 about how their break up had affected the youngest child in their family.
The study found that children of divorced parents were more likely than others to have behavioural problems, mental health difficulties, and were at a greater risk of performing poorly at school.
But the children’s problems were not improved regardless of whether the parents got on well with each other or continued to argue after the divorce, according to the research.