Contextual Value Added Scores

The CVA (Contextual Valve Added) measure is a very important one, introduced into Government performance tables in 2003 initially as VA (Value Added) and then as CVA in 2006. It is more difficult to understand than simple test results, however it is intended to give a more meaningful measure of the impact of a school on the achievments of its pupils. A simple explanation considers two pupils, Pupil A who enters junior school with very high KS1 results and Pupil B who enters junior school with very low KS1 results. Both pupils achieve Level 4 in their SATS at the end of KS2. Exam results do not differentiate between the two pupils, however the CVA score recognises the greater achievement made by Pupil B in "catching up" with Pupil A.

The Value Added (VA) measure considers the progress each pupil makes from KS1 to KS2, regardless of their starting point. The Contextual Valve Added (CVA) measure goes a step futher and takes into account a munber of factors which are outside a school's control but which can affect learning. These are gender, special educational needs, eligibility for free school meals, first language, movement between schools, ethnicity, age within the cohort, whether in care and the level of deprivation in the area where the pupil lives.

The CVA scores for all pupils at KS2 in a school are averaged to produce a CVA score for the school itself. Confusingly, CVA scores lie in a narrow band between 95 and 105 on a seeminly arbitrary scale centered on a score of 100. To make matters worse, the relationship between a school's CVA score and its position in a national ranking table is not linear - 90% of all schools have CVA scores that fall in an even narrower range of 98.5 to 101.5 on the scale. The distribution of CVA scores for all schools nationally looks like this:

KS2 CVA chart

In very simple terms, half of schools have a CVA scope between 99.5 and 100.5. A score below 99.5 should be a concern, and a score below 99 should be a major concern. On the other hand a score above 100.5 is good and a score above 101 is extremely good.

Long Term CVA Trends 2014