The government should drop a "misleading" statistic that suggests up to 1.9 million more pupils in England attend good or outstanding schools than in 2010, a former minister says.
The government says the increase is due to its reforms. But former schools minister David Laws, says it "is simply impossible for this statistic to bear the weight that ministers want to place on it".
The Department for Education dismissed criticism of its use of the figure.
Research by the EPI reveals at least 40 mentions of the statistic by the government "spread across two prime ministers, four secretaries of state for education and numerous ministers".
It also appears frequently in news stories. But closer analysis identifies several factors which "undermine" the statistic's "status as a fair comparison", says the think tank,
In particular, the authors say, more than a quarter of the rise in pupils attending good or outstanding schools is accounted for by an absolute increase in pupil numbers and shifts in the schools which pupils attend. This accounts for 578,000 of the increase, says the EPI.
In addition, the paper says, some 579,000 pupils attend schools rated good or outstanding but which have not been inspected since at least 2010.
Among these are 309,000 pupils at schools which converted to academies and have never have been inspected in their current form.
