Researchers at the universities of Manchester and Stirling analysed survey data on 14,000 children, almost all aged three, and found that the higher the family's income, the better was the children's mental health.
The researchers also found that in better-off families the children's mental health got an extra boost if their parents were higher up in the income ranking than others in their area. However, income rank was not important to children in low- or middle-income families.
The children's mental health was measured using a parent's assessment of aspects of their behaviour, such as depression and hyper-activity. The researchers found that, in families in the highest third for income, being at the top of the income ranking for their area meant the children's overall score for mental health was 39 per cent better than for those at the bottom of the ranking.
Children of parents in the middle third and lower third of income groups weren't affected by the income ranking of their parents.
One of the Manchester researchers, Elisabeth Garratt, told the conference: "We found not just that children aged three have better mental health if they live in better-off families, but that in better-off families the parents' ranking in the scale of income in their region was also important for the child. However, ranked income position was not important to mental health among children in less well-off families.
"Several explanations for these findings are possible. An awareness of ranked income may emerge earlier in the lives of more advantaged children. These children may be more cognitively advanced or there may be a greater importance of income-based status in wealthier families."
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