that her pay rise had been withheld because of the GCSE results of one of her classes, even though her performance more widely had been good.
"Performance-related pay is supposed to be a method for getting teachers to increase their skills and improve their performance," Mr Courtney said. "If you don't tell the teacher that they need to improve, then it's failing the first absolute test and is just being used as a way of saving money."
A separate TESYouGov poll carried out last month shows that almost half of headteachers are dissatisfied with their latest pay rise, despite the number of school leaders earning pound;100,000 or more rising to 900 this academic year, up more than a quarter since 2012 ("Even heads are unhappy with pay rise, poll finds", News, 5 December).
Rob Campbell, principal of Impington Village College in Cambridgeshire, said that although some teachers at his school had not received a pay rise this year, no appeals had been lodged.
"If you have a crude payment-by-exam-results system, it's going to create all sorts of problems," he added. "Schools need to use a broad range of criteria to ensure teachers' cases are fairly considered and fairly applied. This can include the impact in their teaching and their presence in the school community.
"If the appraisal system isn't well set up, it could be problematic. If appraisal is done well, it should be clear to teachers why they have not progressed. They might not be happy, but they should understand how the system is applied."
Patrick Murphy, a history teacher at Wetherby High School in West Yorkshire, who is standing against Mr Courtney in the NUT's next election for deputy general secretary, said that many in the sector had expected no immediate impact from the new system, believing that school leaders would allow it to "bed in" for the first year.
The true scale of the pay restraint could be even greater, Mr Murphy suggested, as teachers might be too embarrassed to admit they have been turned down for a rise.
Craig Vincent, a human resources consultant for law firm Stone King, said most schools were basing their pay policies on a teacher's impact on student outcomes and progress, or their wider contribution to the school.
Teachers who were denied a pay rise because of a school's financial difficulties would have grounds for appeal, Mr Vincent added. "We recommend schools should be budgeting for all individuals to receive pay progression. If people unfortunately don't receive that progression, that money may then be used by schools for other things."
Brian Lightman, general secretary of the Association of School and College Leaders, said he found the NUT's figures "very surprising" as only a small number of appeals had been lodged against pay decisions.
A DfE spokesperson said: "We want the excellent teachers we have in our classrooms to be rewarded in line with their performance - which is why we have given all schools the freedom to set pay so that the best and most successful teachers can progress faster than before.
"All schools are required to set out clearly how teachers' pay is linked to performance and there is no evidence to suggest there are any schools that have not done this. Any school without an appropriate policy will be held to account by Ofsted."
`It has come down to the exam results'
A food technology teacher in West Yorkshire, who does not want to be named, says she was denied a pay rise based on the exam performance of one class.
"No one had a conversation with me to warn me," she says. "I provided a mountain of evidence to show everything I had done that year, but I was told I was being denied pay progression because my Year 11 class hadn't done as well as we'd hoped.
"It was disappointing, to say the least. Everything else I did was fine - all my other classes got good results. I'd only taken over the Year 11 class in January. I did lots of interventions, pulled out all the stops and did everything I could.
"It's not about my overall performance - it's come down to the exam results. You can't just judge teachers on that."