Four hundred staff were questioned by Ipsos MORI for the Qualifications and Curriculum Authority, covering all eight vocational GCSE subjects: art and design, business, ICT, science, engineering, health and social care, leisure and tourism, and manufacturing.
The survey found that 72 per cent of teachers felt fairly or very well prepared. Most had previously taught a vocational or applied subject before the GCSE. But there was a "spectrum" of experience, from these teachers to those who were "unprepared, with very little experience and little support".
One in six of the teachers questioned had never received any training to teach the vocational GCSEs. Among those in their first year of teaching their subject the proportion rose to 40 per cent.
Those teaching business or health and social care tended to feel well prepared, partly because most had experience teaching a vocational subject.
But teachers of science or applied art and design tended to have little or no previous experience. The situation was most severe in engineering, where more than half said they did not feel well prepared.
This lack of preparedness may carry implications for the five vocational diplomas to be launched next year. Ken Boston, the QCA's chief executive, has said that the new courses will stand or fall on the preparedness of staff to teach them.
Alan Smithers, a professor of education at the University of Buckingham, was not surprised. "One of the difficulties with vocational education is ensuring that teachers have the expertise and schools have the equipment to teach it," he said.
Vocational exams count as two GCSEs, but only three in five teachers said the amount of teaching time allocated was twice as long. However, four out of five of those surveyed said that, given the amount of homework, coursework and revision, the equivalence of a vocational course with two GCSEs was right. One in six disagreed, with 37 per cent saying that vocational GCSEs did not require as much work as two traditional courses, while 27 per cent said they were too easy.