Narrower income differences are more likely than economic growth to improve the wellbeing of children in rich countries, according to a study published on bmj.com.
Poorer children fare less well than richer ones in each society. But a recent UNICEF report detailing 40 indicators of child wellbeing, said children in the UK and the USA fared worse than in any of the other rich countries.
The new research examines whether the damage is done by being poor, or by being poorer than others.
To answer this question, academics at The University of Nottingham and the University of York examined whether measures of child wellbeing were most closely related to average income — material living standards - or to the scale of income differences in each society, ie. inequality.
The authors studied these relationships in two different settings: among 23 rich countries, and then, independently, among the 50 states of the USA and District of Columbia.
Among the 23 rich countries, the UNICEF index of child wellbeing - covering material wellbeing, health and safety, educational wellbeing, family and peer relationships, unhealthy and risky behaviours, and subjective wellbeing - was unrelated to average income, but was strongly related to the size of the income differences between rich and poor within each country.
Findings were similar among the 50 states of the USA. Data were analysed for teenage births, juvenile homicides, infant mortality, low birth weight, educational performance, high school drop-out rate, the proportion of children overweight, and mental health problems. All were more strongly related to the scale of income inequality in each state than to its average income.
Richard Wilkinson, Professor of Social Epidemiology at The University of Nottingham Medical School, co-authored the paper with Dr Kate Pickett of the University of York.