Exam assessors fear many more schools may have to produce their own prelim papers, after the Scottish Qualifications Authority barred them from working for commercial producers of exam papers on "conflict of interest" grounds.
Although the SQA dismissed concerns about the impact on schools as a "red herring", one assessor, who asked not to be named, told The TESS: "Unless the SQA changes its stance before next session, we face the prospect of schools having to create their own prelims on a year-to-year basis - a very onerous task in some subjects."
There are a number of companies of various sizes producing prelim papers. The best-known is Pamp;N Publications, based in Bannockburn, which has 60 teachers on its books; another widely used company is Aberdeenshire-based Perfect Papers.
The assessor claimed reputable firms would struggle to find quality setters and produce papers at the right level, adding: "I just don't get it - I can't understand where the supposed conflict of interest lies."
An SQA spokesman said: "These aren't new guidelines. We've always sought to avoid conflicts of interest, which arise when SQA appointees wish to become involved in third-party commercial interests.
"Last year, we became aware that some weren't adhering to the agreed policy, and we have been obliged to issue reminders."
He added that, of nearly 1,000 examining team appointees, only 20 had indicated they might have conflicts of interest.
It was a "red herring" to suggest schools would have to rely on less reliable evidence for appeals: "Indeed, it is already clear from the submission of assessment appeals evidence that many schools are presently in a position to devise valid assessment materials that replicate that of the SQA examination."
There was not necessarily a need to create brand-new prelim papers: SQA guidance allowed for "judicious selection" of questions from past papers - "preferably adapted" - provided they were drawn from at least three different papers, he said.
Ann Ballinger, general secretary of the Scottish Secondary Teachers' Association, said: "We've had an increasing number of calls from assessors and principal assessors who are having problems with the SQA, including various payment and contractual issues, which we've never had before."
If complaints about the SQA continued to come in regularly, Mrs Ballinger predicted, the qualifications authority would face "huge difficulty" in recruiting teachers.
But the SQA said it had received 1,870 applications from teachers "keen to assist us in the development, assessment and quality assurance of our qualifications" for 2009-10.
"Any fears that we might not be able to recruit professionals to assist us in the successful delivery of Scotland's national qualifications are unfounded," its spokesman said.