Reception teachers have been given the wrong advice by some education authority advisors on how to assess five-year-olds' abilities, a Qualifications and Curriculum Authority monitoring report has revealed.
The conclusions add further weight to complaints from early-years staff that confused advice has marred the introduction of the early-years foundation stage in October 2008.
Since 2003, every child has been assessed at the end of reception against 13 nine-point scales, which rate skills ranging from linking sounds and letters to how well they get on with others. Local authorities are responsible for moderating these judgments to ensure they match around the country and setting targets based on them.
But now, the QCA has slapped down local authorities for producing their own exemplification material that did not match national advice and "which may lead to confusion and inaccurate judgments".
Margaret Edgington, an independent early-years consultant and member of the Open Eye campaign, said: "There is still lots of confusion - I am still picking up the rumour that three pieces of evidence are needed for each scale point.
"But local authorities are also under great pressure, because while the QCA is responsible for the profile, the National Strategy advisers are going round policing the local authority targets and I am not sure how much the QCA and National Strategies talk to each other.
"There is a lot of pressure on local authorities to raise outcomes. They can't do it by themselves so, in the end, they have to pressure schools and the settings that feed into those schools."
Concerns are also being raised about the reliability of data, from scores being inputted wrongly, difficulties with moderation and schools "inadvertently depressing" results in order to boost value-added scores.
The QCA's guidance on quality assurance reveals that when the London borough of Havering asked heads to recheck their 2007 data before it was sent to the Department for Children, Schools and Families, 44 per cent of schools made changes - mostly correcting typing errors.
The QCA's 2008 monitoring report on the assessment process found only 61 per cent checked that practitioners understood scale points. Additionally, just one in four local authorities did not have suitably qualified staff involved in the moderation process last year, an improvement on 2007. When almost two-thirds of authorities did not have suitably qualified moderators.
The QCA's monitoring report in 2007 said there were concerns that target- setting could lead to the "pursuit of narrow and inappropriate outcomes".
Moderators reported that some schools were trying to link the foundation stage profile scores to national curriculum levels, which could lead to an "inadvertent depressing" of scores by school management.
The authority warned: "Such activity challenges the accuracy and validity of the data and critically undermines its fitness for purpose."
Last year, there was a sharp improvement in the proportion of authorities demonstrating the most effective practice in supporting early-years assessment. The strongest areas were engaging in inter-authority moderation events and identifying new staff, both of which more than nine out of 10 authorities did.