Marking errors affect CVA

John Dunford wrote to Ed Balls in September alerting him to the damaging effect that Key Stage 3 test marking errors were potentially having on schools' Ofsted inspections. The letter also went to Ofsted chief Christine Gilbert and QCA chief executive Ken Boston.

ASCL pointed out in the letter that schools can only submit individual or group reviews for key stage tests if they believe students have been awarded the wrong level. However, the DCSF uses detailed key stage marks, rather than broad grade levels, to determine contextual value-added (CVA) scores.

Members have informed ASCL that they have uncovered errors which would change the marks significantly but not at a point that would affect the grade level. This could result in the school's CVA being calculated incorrectly yet the school has no means of redress. An incorrect CVA, of course, can have a detrimental effect on the Ofsted grading.

In the letter, John Dunford said, "These concerns have been expressed to us previously, but school leaders are voicing them more strongly in light of this year's problems. An early reassurance that these problems are being addressed would be welcome."

ASCL also sent evidence to the Sutherland inquiry into the summer's exam problems but has told ministers that the inquiry does not go far enough.