The head of the UK's statistics watchdog has written to the education secretary to raise "serious concerns" about his department's use of statistics.
Sir David Norgrove, chair of the UK Statistics Authority, issued a stinging rebuke to the Department for Education (DfE), which he said had misused statistics on at least three occasions in recent months.
He accused ministers of having made inaccurate claims about improvements in children's reading, levels of school funding and the number of pupils in good schools.
Sir David said DfE "does not appear to have resolved issues with its use of statistics".
In a letter to Damian Hinds, the education secretary, he wrote: “I am writing to raise with you serious concerns about the Department for Education’s presentation and use of statistics.
“The UK Statistics Authority has had cause to publicly write to the department with concerns on four occasions in the past year. I regret that the department does not yet appear to have resolved issues with its use of statistics.
“I seek your reassurance that the department remains committed to the principles and practices defined in the statutory Code of Practice for Statistics. In particular, I urge the department to involve analysts closely in the development of its communications, to ensure that data are properly presented in a way that does not mislead.”
Labour said the letter was a "humiliating rebuke" and demanded the government "stop deceiving the public".
Criticising the blog, Sir David said the figures "were presented in such a way as to misrepresent changes in school funding", including by referring to "a wide range of education expenditure unrelated to publicly funded schools, rather than a comparison of school spending alone".
He wrote: "The result was to give a more favourable picture. Yet the context would clearly lead readers to expect that the figures referred to spending on schools."
The data had been misrepresented in a graph and had not been adjusted to reflect spending per pupil, he added.
The watchdog chief also criticised the department's claims about an increase in the number of children in high-performing schools, as assessed by Ofsted. While the statistic was fundamentally accurate, he said, it did not take into account an increase in the total number of pupils or changes to the way schools are inspected.
Responding to Sir David, Mr Hinds said his department was "looking into the precise issues that you raise" but defended its use of statistics.
He said it was "true to say that the OECD has ranked the UK as the third highest for total education spending - the figure which includes tertiary and private education for every country".
He also insisted the UK's child literacy ranking had improved, but admitted: "We agree that we could have been clearer that the improvement from 19th to 8th was between 2006 and 2016."
And he said the proportion of pupils in schools ranked "Good" or "Outstanding" by Ofsted in their last inspection "has risen from 66 per cent in 2010 to 86% in March 2018".
Labour said Sir David's rebuke was "humiliating" for the government.
Angela Rayner, the shadow education secretary, said: “This is a humiliating rebuke for Tory ministers. The education secretary has not even been in office for a year, yet this is the fourth time he has been caught by the government’s own watchdog making a claim that is wildly misleading or blatantly false.
“They need to come clean and stop deceiving the public in a desperate attempt to cover up their shocking record.She added: “They have used misleading figures on school funding to hide the fact that they have cut billions of pounds from school budgets, leaving head-teachers forced to beg for donations from parents to pay for books and stationary.
“And their claims on school standards are now in tatters. Instead of relying on discredited statistics they should use the Budget to invest in schools and genuinely improve standards.”
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