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Child development and marital status

Researchers: Professor Alissa Goodman

Project overview

The Institute for Fiscal Studies (IFS) examined data on 10,000 three and five year olds and concluded that developmental differences between children born to married parents and those born to unmarried parents are not primarily accounted for by marital status, but determined by other factors, such as parental age, education, and income.

Factors such as education, income and occupation are significant in whether people choose to marry or to cohabit, which is why it can appear that children born to married parents achieve better outcomes, but the evidence shows that once these differences in parental characteristics are accounted for, parents’ marital status appears to have little or no impact on children’s cognitive development. Even in the case of children’s social and behavioural outcomes, where relationship quality is important, the question is whether marriage causes or results from better quality relationships.

Additional analysis

The IFS undertook additional analysis using a different dataset to ensure the effect of marriage had not been underestimated.

Researchers used data from parents’ own childhoods to identify difference between couples before they entered before they entered into the relationship into which their child was born. After controlling for these differences, they found no significant difference in the development of children born to married parents and those born to cohabiting parents.

Researchers found that parental cognitive ability was the most significant factor in children’s development. The higher average cognitive ability of married parents over cohabiting ones explains about one fifth of the gap in the cognitive development of children.

Latest on this project


  • Professor Alissa Goodman
    Institute for Fiscal Studies

  • Director, Welfare
    Nuffield Foundation

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