The Office for Standards in Education has been at the centre of controversy for the six years of its existence, yet the latest piece of research - which follows on the heels of surveys by the National Union of Teachers and a MORI poll - suggests it has convinced most teachers that school inspection is now part of the culture.

A review carried out on behalf of the self-appointed Office for Standards in Inspection, an anti-OFSTED pressure group, suggests that while inspection is expensive and affects heads and teachers negatively, parents think it will improve schools, and many governors view it favourably.

The project was directed by Maurice Kogan, of Brunel University, and Margaret Maden, of Keele University. It sent questionnaires to more than 2,000 English schools, conducted case studies in schools and interviewed governors and representatives from government agencies, teachers’ unions and local authorities.

While the report argues for schools having a greater role in self-evaluation, it also acknowledges the achievement of OFSTED in promoting acceptance of an “inspection culture”.

The major failings of the present system, says the report, are the difficulty of identifying improvements in standards that come about as a result of inspection (though the benefits are more apparent where schools are failing); and the annual bill of more than pound;100 million.

The report sets out for the first time the costs of inspections - not only those incurred by OFSTED, but also those of local education authorities and schools.

It calculates the total cost of inspecting a medium-size secondary school to be about pound;65,800, of which OFSTED’s share is pound;27,000. The authors say it appears that more is spent on inspection than on staff development.

It is reckoned that local education authorities spend between pound;1,450 and pound;1,810 on pre-inspection work with each of their secondary schools. And 20 per cent of additional teacher time is taken up with preparation in the three months before inspection. (In future schools will have less notice of their inspection date.) The report criticises the system of contracting for school inspection and the employment of freelance inspectors. It notes that teachers in particular report a high degree of variability between teams, which might be a result of OFSTED having 16,000 inspectors on its books.

Few teachers felt that the OFSTED process was either valid or fair. One said: “It’s just a snapshot and not the whole film. It is squeezed into one week; aspects are not going to be seen, and judgments are made by people you don’t always respect for their experience, professionalism or approach. They can damn a school for a very long time.”

The extent to which inspection can bring about improvement was raised with heads, governors and parents. On the whole, heads did not think inspections had contributed to improved results. Governors were more divided, with a third saying that inspection had led to an improvement. Two-thirds agreed, however, that it had helped the school focus on areas needing development.

The disadvantages of inspection, the report says, are the stress felt before inspections and the increased absences in the three months after them. Some schools thought that inspections had resulted in retirements and resignations.

Teachers said that the system undermined morale and confidence as it was punitive and fault-finding. They also resented the extra paperwork that it entailed. One head said: “Heads work with sensitive staff and pick those who are dedicated. People who care are more vulnerable and it is difficult to carry them through.”

Nearly half the teachers interviewed said that the variabilityof inspection teams was a major weakness. One said: “How canit be called an office of standards when there is such variation (between teams)?” Professor Maden commented that there ought to be more dialogue between inspectors and schools. “The system is a bit ramshackle,” she said. “Even given OFSTED’s best efforts, it is difficult to get consistency across inspections.”

But despite the criticisms, the researchers found that the inspection guide for inspectors - had given schools a tool for self-evaluation and had helped improve management systems.

The extent to which OFSTED contributes to raising standards remains unclear. But what the research does clarify is that the reaction to OFSTED is mixed, with parents, governors and teachers all holding different views.