Primary value-added measures are misleading, biased against more able pupils, and will never be able to reflect accurately the efforts of most schools, new research claims.
The study, commissioned by the National Association of Head Teachers, calls for key stage 2 value-added measures to be scrapped this year and the whole issue of primary performance tables to be re-examined.
David Hart, NAHT general secretary, wants the Government to talk about the future of the system. "In the longer term they are simply going to have to listen," he said.
The research, by Peter Tymms and Colin Dean from Durham university's curriculum, evaluation and management centre, lists several concerns about how the progress children make the ages of seven and 11, is measured.
The main problem with the system, introduced last year, is the small size of many primaries. Currently value-added data is published for schools with as few as 11 pupils in a year group, which the study says can lead to "wild fluctuations" in the figures from year to year. It recommends that data should not be published for schools with year groups of fewer than 50 pupils. Dr Dean estimated this would rule out more than 80 per cent of primaries.
Schools with many able seven-year-olds are also penalised. The top of the scale for KS2 is level 5. The brightest pupils achieve level 3 at KS1.
Under the value-added system pupils who move from level 3 at seven to level 5 at 11 are judged to have made average progress. They cannot register a better-than-average value-added score.
The study identifies concern among heads about the quality of KS1 data and says that separate junior schools are likely to suffer in comparison with primaries because infant schools will push harder for good KS1 test results.
High pupil turnover meant that some schools, for example those with parents in the armed forces, had valued-added scores that did not reflect their efforts.
School standards minister David Miliband said that value-added information had been widely welcomed as a significant step forward.