Head teachers have demanded an end to the annual publication of school league tables in England.
Jane Cambrook: "Needs of pupils are seen as irrelevant"
They complained that the data did not give a clear information about schools, especially if they took in children with learning difficulties as a matter of policy.
Delegates at the National Association of Head Teachers conference called on their national council to pursue the abolition of league tables.
They stopped short of calling for a boycott, which the National Union of Teachers conference did over Easter - and which would be illegal.
But there was thunderous applause for the union's president, Gareth Matthewson, when he told visiting education minister Stephen Twigg that Westminster should follow the example of the Welsh Assembly government in scrapping the tables.
Keith Davies, head of Tidbury Green school in Solihull, said performance tables could never give clear information and were often misleading.
He said the government was trying to treat schools as if they were boils.
"It squeezes schools, and because squeezing boils doesn't make them better it sets higher targets and squeezes them more.
"When will the Westminster government realise that the more a boil is squeezed the more damage is caused and the longer it takes to heal?" he said.
Ian Foster said his school - Leominster Junior - had a successful, integrated unit for children with moderate learning difficulties.
But no account was taken of this in the tables.
"We drop about 5% each year because of our inclusive ethos and intake," he said.
Another concern was the way children who were absent - ill or on holiday - when the tests were taken were still counted in the results.
"Why should schools be penalised because parents have found a package in May that's half the price they will pay in August?"
It was a sad state of affairs that the needs of individual children were lost in the relentless pursuit of government statistics, he said.
Others complained that some heads and deputies condoned the whole business by running booster classes in preparation for the tests during the Easter holidays, when they and the tired children should have had a break.
Jane Cambrook said a head teacher she represented had asked the Department for Education how the school might mark the performance of an 11 year old whose mother had died just before the tests.
She was told it was impossible to take account of his usual work.
"Why? - 'Well, you head teachers might think up all sorts of excuses like this to improve your results'," was the reply.
Ms Cambrook said this showed her two things: the profound lack of trust in the professional integrity of head teachers.
"And that this is a system in which the needs of the individual pupil are seen as irrelevant."
England alone in the UK publishes tables for primary and secondary schools.
Scotland still publishes secondary tables, but they have been abolished in Northern Ireland and in Wales.