The moves to reform A-level and GCSE exams in England are taking place without trials or tests to see if they are workable. The problems with Curriculum 2000 led to the conclusion that pretesting was vital to ensure that exam reform was feasible. But this is not being done despite the great risks of changing both levels at once. This has never been attempted before.

Indeed, Glenys Stacey, the head of exams watchdog Ofqual, told a conference I recently attended that there was no point in pre-trialling the qualifications. In her view, this would not have prevented the 2012 problems with GCSE English. If this is the official position of Ofqual, the conclusion must be that in England we can only proceed by trial and error. This is dangerous. The government is seeking more demanding exams with no indication that the reforms will work. There is no point in trying to fly higher if the engines are liable to fail on take-off.

Trevor Fisher, Stafford.