Provided by University of Birmingham Research Archive, E-prints Repository
'This is an electronic post-print version of an article published in Educational Review
Vol. 60, No. 2 (May 2008): 179-185. Journal of Education Policy is available online
at: http://www.tandf.co.uk/joumals/titles/0013-1911.asp.
URL to published version: http://dx.doi.org/10.1080/00131910801934185.
The value-added of primary schools: what is it really measuring?
Stephen Gorard
School of Education
University of Birmingham
B15 2TT
Abstract
This paper compares the official value-added scores in 2005 for all primary schools in
three adjacent LEAs in England with the raw-score Key Stage 2 results for the same
schools. The correlation coefficient for the raw- and value-added scores of these 457
schools is around +0.75. Scatterplots show that there are no low attaining schools with
average or higher value-added, and no high attaining schools with below average value-
added. At least some of the remaining scatter is explained by the small size of some
schools. Although some relationship between these measures is to be expected - so that
schools adding considerable value would tend to have high examination outcome scores
- the relationship shown is too strong for this explanation to be considered sufficient.
Value-added analysis is intended to remove the link between a schools’ intake scores
and their raw-score outcomes at KS2. It should lead to an estimate of the differential
progress made by pupils, assessed between schools. In fact, however, the relationship
between value-added and raw scores is of the same size as the original relationship
between intake scores and raw-scores that the value-added is intended to overcome.
Therefore, however appealing the calculation of value-added figures is, their
development is still at the stage where they are not ready to move from being a research
tool to an instrument of judgement on schools. Such figures may mislead parents,
governors and teachers and, even more importantly, they are being used in England by
OFSTED to pre-determine the results of school inspections.
Introduction
Much has been written about the problems involved in making comparative claims
about the relative effectiveness of schools with equivalent pupils (Gorard 2000, 2001,
2005). There are difficulties in assuming that the indicators of school outcomes are
comparable across time, place and curriculum area. There are also difficulties in
equating outcomes scores for pupils at one age with scores at a later age. These