Using taxpayers' money to repay teachers' student loans has done little to improve recruitment and retention, according to a government-funded study.
Many trainee teachers are unaware of the inducement, it found.
Fewer than one in 10 teachers benefiting from the repayment of teachers'
loans scheme said its existence influenced their decision to enter the profession. And only one in nine said it had persuaded them to stay in teaching when they might otherwise have left.
The study of the views of 246 teachers was carried out by Patrick Barmby and Robert Coe of Durham university.
The scheme was introduced as a three-year pilot in 2002 after ministers faced criticism that student debt would discourage graduates from entering teaching.
It entitles newly-qualified teachers of shortage subjects, English (including drama), mathematics, foreign languages, design and technology, information and communications technology, science and Welsh to have 10 per cent of their student loan written off for each year they remain in teaching.
Last month Stephen Gorard, of York university, told the British Educational Research Association that money spent on "golden hellos" and training salaries had been wasted.
Recruitment analysts estimate the schemes have cost up to pound;800 million since they were introduced four years ago.
Both Professor Gorard and the Durham university study found that improvements in workload and pupil behaviour were of greater importance to recruitment.
Teachers were generally positive about the repayment scheme, but they wanted to see it more widely advertised and called for the paperwork associated with it to be simplified.
Phil Willis, the Liberal Democrat's education spokesman, accused the Government of adopting a "knee-jerk" approach to tackling the profession's recruitment problems.
"This money would be better spent ensuring teachers have the tools to do the job when they arrive. That means smaller classes in primaries," he said.
Evaluation of the Repayment of Teachers' Loans Scheme by Patrick Barmby and Robert Coe is available at www.dfes.gov.ukresearch