The Government was accused this week of wasting millions of pounds on flagship qualifications nobody wants.
Previously unpublished figures show more than 40 per cent of the much-vaunted national vocational qualification courses have either been completed by just one trainee - or by no one at all.
Opposition leaders, squaring up for a final week of electioneering, condemned the state of the qualifications, more than a decade after they were set up.
The Government has poured Pounds 79 million into the much-criticised NVQ system at a time of deep cuts in schools and other parts of the education system.
The figures, showing NVQs awarded up to September, show that of the 878 awards currently available, 330 have never been completed, and another 50 have been completed just once.
A small number of awards are very popular. Some 23 NVQ subjects have been awarded to more than 5,000 people, while 91 have produced more than 1,000 certificates.
Shadow education minister Stephen Byers said the figures were "startling" and attacked the Government for wasting public money, promising a full review of the system.
He said: "There's clearly an element of public money being wasted and we condemn the Government for allowing it to happen. It's money from the education system that could have been used for better purposes.
"The Government did not consult enough with employers and business to find out whether the specific NVQs were necessary. We want to look again at NVQs. We need to have a proper review of exactly how NVQs are regarded by employers and employees."
Liberal Democrat education spokesman Don Foster said: "The figures show exactly what I pick up from employers. It's exactly like the overcrowded national curriculum - there are too many qualifications in too tightly defined areas and we need a simplified system."
The Lib Dems promise complete reform of qualifications to sweep away the academicvocational divide through a credit transfer system.
Ministers have acknowledged some of the failings of NVQs and have made a revamp of the system a Tory manifesto pledge.
The Tories insisted the figures showed that overall, NVQs were a success story. A relaunch of the revised NVQ is planned for summer if the Conservatives win the election.
Professor Alan Smithers, of the Centre for Education and Employment Research at Brunel University, and a persistent critic of vocational education, said the figures were "dramatic" and showed around Pounds 30 million, 40 per cent of the development costs, had been wasted.
He said: "The drive for these has not come from employers. They have not seen a need for them nor put money into them.
"It has been policy to establish them, and state money has gone into lead bodies and awarding bodies, so there has been an incentive for them to keep on planning them. It looks as though the market has decided against them."
Professor Smithers has long argued that NVQs are too heavily based on narrow job descriptions - with the result that a few qualifications, such as those in hairdressing and business, are popular, while many more have very low take-up rates.
But a spokeswoman for the National Council for Vocational Qualifications, soon to merge with the School Curriculum and Assessment Authority, said the figures only related to the number of NVQs completed, not the number of people working towards them. She argued that the time lag between setting up an award and getting courses and assessment running could be a factor in the take-up figures.
She acknowledged that there was little way of establishing how many people were studying for any given award, but said: "If there are little or no certificates on a programme then serious questions would be asked about it."
NVQs have been plagued by criticism throughout their 11-year life. Only last autumn Peter Robinson, of the London School of Economics, suggested that only 660,000 people were involved in NVQs - a figure hotly disputed by ministers, who claimed a take-up of around 2 million.