The TES survey shows that two out of five schools (41 per cent) have paid for pre-inspection advice with almost one in 10 (9 per cent) paying more than Pounds 2,000.

The evidence from the survey and from comments made by heads shows that while the experience of being visited by the Office for Standards in Education was often stressful and traumatic for the staff, most found the inspection fair and 82 per cent believe it contributed to improvement at their school.

Katherine Samad of Princess infants in Manchester’s Moss Side, said: “We believe inspection will contribute to an improvement in standards, but only in that it strengthens the ability of senior management to put into practice the changes it perceives to be necessary. Most schools are aware of what needs to be done. OFSTED usually confirms what we already know.

“Chris Woodhead has helped improve standards by giving senior management teams the necessary power to be able to say ‘OFSTED has said that we need to do’. . .”

Of the sample, 38 per cent of primaries, 80 per cent of secondaries and more than half the middle schools had been inspected. And when asked if their report was, on balance, fair, 84 per cent of primary heads said yes, as did 94 per cent of secondary heads and all those in middle schools.

Headteachers are also, in the main, satisfied with the inspection team despatched to their school, with secondary heads slightly more impressed (88 per cent) than their primary colleagues (79 per cent).

However some heads did comment that not every member of the team came up to scratch- one secondary head from Cirencester described it as “a mixed bag”.

Chris Woodhead, the chief inspector, received less support. Only one in five heads believe he is helping to raise standards. One head commented: “OFSTED yes, but [Mr Woodhead’s] speeches no.”

However, Mr Woodhead, who has lost friends in the profession after criticising standards in schools and claiming 15,000 teachers should be sacked, may be surprised to find as many heads as this who believe he is doing a good job.

The controversial Mr Woodhead provoked much comment: “Chris Woodhead’s views appear to be coming unhinged from normal HMI standards focused upon clear evidence and research . . . his use of unsubstantiated evidence or his personal prejudices will get in the way of rational and careful analysis and debate, ” said Ian Kershaw, head of Sidney Stringer community technology college, Coventry.

And an infant school head from Shropshire said: “Mr Woodhead has created a climate of negativism. Constant criticism amd emphasis on failing areas without appreciating good areas will not create the positive climate necessary for real progress and improvement.”