It concludes that pressure to coach pupils towards the tests and to achieve good results in them is undermining the curriculum.

The study was carried out by the Association of Teachers and Lecturers, working with the National Association for the Teaching of English and the Association of Teachers of Mathematics. It was based on nearly 550 responses from teachers to a questionnaire about English and maths tests at Key Stage 3, followed by two focus groups which met after marked scripts had been returned to schools.

The authors say that the tests tend to turn off pupils of lower ability, producing a negative attitude towards further learning.

Many teachers, they say, still believe that formal assessments by them would be more useful.

'Unreliable'

There are also "serious concerns" about the validity and reliability of the tests and about the quality of external marking, particularly for English.

The association notes that this tends to confirm remarks by the Chief Inspector of Schools in England, Chris Woodhead. Mr Woodhead said in a seminar in the London School of Economics that the tests needed to be more "standardised", that year-on-year comparisons were unreliable and that there were problems with how they were administered by teachers in the classroom.

QCA: Under fire

The authors of the new study say "the purposes to which national test results are now being put is profoundly de-professionalising, subverting good practice in assessment and, consequently, in the process of teaching and learning."

Their conclusion is that "the ultimate losers are the pupils themselves."

The association's General Secretary, Peter Smith, said: "The Qualifications and Curriculum Authority must, as a matter of urgency, review the way tests are both set and marked. What have they got to hide?