They also seem to be behind their peers in other countries, albeit a conclusion based on very limited comparisons with three education systems.
Even where the pre-school stages were found to be having a positive impact, on maths scores for pupils entering primary, the effect was marginal.
For a Government that has invested millions in extending pre-school education and milked the achievement for all its worth, this is depressing news. But, although the researchers reach the predictable (and classic) conclusion that there now needs to be further research, perhaps it is the research itself that requires scrutiny. If most three and four-year-olds have a pre-school education, and most for half a day, it is surely predictable that there will be little difference between them when they start school. Most children, in other words, have the same amount of pre-school experience and the precise impact of that experience will therefore be difficult to gauge, although no doubt the quality of it varies.
The question of whether pupils should be further ahead in literacy and numeracy when they start primary school is a different one. Benchmarked against other countries, our children do not seem to be doing so well. But, as with all international comparisons, the pitfalls of such studies have to be recognised. If curricula and teaching differ from country to country, as they do, any measurement of how pupils perform has to take account of that; studies showing pupils in some countries performing better than others may be testing activities which have a stronger role in some countries than in others.
This is a complex area and, in one respect at least, the researchers are right: we need further research.