PUBLISHING school league tables can narrow the curriculum, force teachers to concentrate on borderline pupils and increase the blame culture, according to new research.
A comparison of the experience of primaries in England, where national curriculum tests are published, and Scotland, were results are not made public, found performance tables could be harmful to schools' longer-term management and organisation.
The study by Durham University of 54 schools found that primaries from both countries wanted access to good data and felt pressure to improve standards.
But the English primary schools reported conflict between their aims and their targets.
Subjects like PE and art were sidelined because of the need to concentrate on the core skills of English, maths and science. Opportunities to develop personal and social skills were also reduced.
Children who were just below the level expected of their age group were the focus of attention in the classroom in a bid to improve league table positions at the cost of working with special needs orgifted pupils.
The research also found that league tables may contribute to a "blame culture" in schools, reducing co-operation and trust between staff and schools.
Report author Professor Peter Tymms said: "There has been very little research of this type in the educational field but evidence from other public-sector and commercial organisations suggests that publishing performance data can be harmful.
"The differences we found were statistically significant and lead us to conclude that publishing school performance data can have long-term dysfunctional consequences."
Mick Brookes, president of the National Association of Head Teachers, said the research backed up the association's view that league tables harm schools.
"Performance data is really useful stuff for schools but the way it is being used is having a negative effect, particularly on schools in the toughest areas. We hope the Government will take this research seriously."
This year's key stage 2 test results will be published in December.