Dr Christine Merrell, Professor Peter Tymms and Dr Paul Jones analysed the results of 35,000 children doing the same assessment tasks in 124 primaries from 2001 to 2006.

They found that the overall development and skills of children remained stable, with the only significant change over time a very slight decline in vocabulary.

There was no indication that the gap in achievement between children from deprived and affluent backgrounds was decreasing.

They state: “On one hand one might expect that the major initiatives would have resulted in measurable changes, on the other it is important not to jump too rapidly to evaluative conclusions.”

The team pointed out that during and immediately before the five years of the study there had been several national and local initiatives designed to help children do better. These included the Sure Start local programmes, begun in 1999, the introduction of the foundation stage curriculum in 2000 and Every Child Matters in 2003.

But they added they had no measures of how many children in their study were involved in these initiatives and that it is known that influencing the development of young children is not easy.

Beverley Hughes, children’s minister, said it was too early to measure the scheme’s results.

The first large-scale study of Sure Start published two years ago revealed that the most disadvantaged groups fared worse in Sure Start areas than similar parents elsewhere. It had more positive news for less deprived families, finding children scored higher for verbal ability and parents were less inclined to shout at or slap children.

In a report this week, Ofsted found more than a third of childcare providers inspected need to do more to support children’s learning. Activities need to be better adapted to individual needs and there should be more opportunities for imaginative play, inspectors recommended.

The proportion of settings rated as good or outstanding at helping children achieve fell to 70 per cent, down three percentage points on last year.

The proportion of childcare providers described as good or outstanding overall fell to 57 per cent, down four points.

Christine Gilbert, head of Ofsted, said almost all childcare providers were maintaining high standards. “It is important to highlight that there have been many improvements across the sector this year, but where provision is inadequate we will continue to monitor those providers and take enforcement action,” she said.

Inspectors received 960 complaints from parents. In one case, a member of staff attempted to take a child home even though the parent had not given consent.

In other examples, parents complained of a child being restrained in a high chair and another child with special needs being neglected.

Ofsted has the power to investigate complaints and can, in the most serious cases, close down childcare providers and bring prosecutions.

* Changes in Children’s Cognitive Development at the Start of School in England 2000 to 2006. Presented at the European Association for Learning and Instruction (Earli) conference

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