FEWER than one in 10 heads and deputies thinks the time and stress preparing for an inspection is justified by the value of the final report, a union survey has found.
According to responses from 1,250 members of the National Union of Teachers, only one in five heads and deputies believes that inspections lead directly to improvements in their schools.
But more positively for OFSTED, teachers were evenly divided on whether inspectors' final judgments were fair and accurate.
Most (47 per cent) also agree that OFSTED inspectors established a professional dialogue with teachers, while 45 per cent believe the inspectors take into account circumstances which affect schools but are beyond their control.
Comments from respondents revealed staff who made an effort and "stage managed" the event did well, but some good teachers who wanted inspectors to take them as they found them were criticised.
One head who took over a school which had been criticised by inspectors agreed with them, but said the report left staff, including talented teachers, demoralised.
Another said: "The team we had was really aggressive. It was led by two inspectors who had to be taken to one side and asked if they had been sent to start World War III. Hopeless and very poor value for money."
Doug McAvoy, NUT general secretary, said: "The extra work and stress created by OFSTED inspections might be justified if the process and outcomes were valued by teachers and led to school improvement. But head and deputy head teachers clearly do not believe this is the case.
"The level of dissatisfaction with OFSTED inspections is very high. Familiarity with the system had not lessened their objection to the disruptive and arbitrary character of OFSTED inspections."