James Boardman, professor of neonatal medicine at the University of Edinburgh’s MRC centre for reproductive health, who led the study, said the findings highlight the need for government policies to address the social factors hampering SLC (speech, language and communication) development and impact on employment opportunities.
A team from the university and NHS Lothian looked at more than 26,000 records of children who had a routine health review between 27 and 30 months between April 2013 and April 2016.
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It is believed growing up in neighbourhoods with low income and unemployment – experiencing problems with education, health, access to services, crime and housing – can increase setback risk.
Researchers also discovered that each week a child spent in the womb from 23 to 36 weeks was associated with an 8.8 per cent decrease in the likelihood of them having an SLC concern reported at 27 months.
The study used birth data from children born in the Lothians but experts say similar results might be expected across the UK.
"More could be done to lessen the number of children having this problem"
Prof Boardman said: “The NHS does have excellent facilities for children identified as having a problem pre-school. But more could be done by having economic policies designed to lessen the number of children having this problem.”
The study, released during Challenge Poverty Week 2019 which sees organisations ranging from the NHS to the Church of Scotland debate and debunk myths about poverty, was part-funded by the Medical Research Council and is published in the journal JAMA Network Open.
John Dickie, director of Child Poverty Action Group in Scotland, said: "This is one more compelling piece of evidence why eradicating child poverty must be a top priority for government at every level.
"Poverty in Scotland is entirely preventable" - John Dickie, director, Child Poverty Action Group in Scotland
"No child's development should be undermined by poverty.
"Poverty in Scotland is entirely preventable. We need to see more action to tackle the low pay, insecure and irregular hours and hopelessly inadequate social security that locks so many children in poverty and causes such harm."
"Measures to mitigate the worst impact of UK welfare cuts"
A Scottish Government spokeswoman said: "Improving the education and life chances of all our children and young people – irrespective of their background – is one of the defining missions of the Scottish Government. That’s why we are investing £750 million during this Parliament to ensure every child has an equal chance to succeed.
“We have taken a range of measures to tackle the attainment gap, including investing more than £1.4 billion in 2018-19 to support low income families – of which £100 million was spent to mitigate the worst impact of UK welfare cuts.
"Our recently announced Scottish Child Payment, worth £10 per week per child, is a further example of our transformative action to tackle child poverty. When fully rolled out, this investment will put more than £1,000 a year in the pockets of a two-child family, and will lift 30,000 children out of poverty.”