Study finds marriage has no bearing on children's outcomes

The research, which was funded by the Nuffield Foundation, was based on the data of 10,000 children around the country. Although the study found differences between the development of children of married and non-married parents, it found that these were attributable to the differences in the sorts of parents who decide to get married rather than cohabit, not the experience of marriage itself.

The Institute of Fiscal of Studies research author and senior economist Alissa Goodman said: "Our findings do indicate that children who have married parents compared to co-habiting parents have significantly improved outcomes. Their cognitive development is more advanced and there is an even bigger gap in social and emotional development."

But these differences are due to married parents being more educated, having a higher household income, a better job and stronger relationship during the child's early life, according to the findings. The study suggests that it is these factors that lead to better outcomes for their children, therefore questioning the causal evidence that links marriage to the improved outcomes of children.  

"These differences in socio-economic status and relationship quality between married parents and co-habiting parents seem to account for the differences in their children's development."

"Our findings indicate that even if more couples decide to get married because of a financial incentive that would probably have very little difference on children's outcomes," she added.

The Conservative Party pledged its policy to reward married couples through a tax break last week in its 2010 election manifesto.