Ofsted should scrap the “quality of teaching” category from its inspection reports as it leads inspectors to “impose” their preferred teaching styles on schools, according to a report released today.

Research published by right-leaning think tank Civitas claims that Ofsted inspectors continue to ignore the pleas of their chief inspector and insist on encouraging so-called “trendy teaching” methods, such as child-led learning.

Back in January, Ofsted’s head Sir Michael Wilshaw wrote to his inspectors saying: “Please, please, please think carefully before criticising a lesson because it doesn’t conform to a particular view of how children should be taught.”

But according to the report’s author, Robert Peal, inspectors still insist on promoting “non-traditional” methods of teaching in classrooms.

Mr Peal, who taught for two years as part of Teach First and is about to start work in a free school, said the continued existence of a preferred teaching style was of the most “pressing concern” for classroom teachers, and called for the quality of teaching category to be abandoned.

“What Ofsted inspectors criticise and praise is invariably based on personal preference,” Mr Peal writes. “Schools and teachers should have the freedom to accept or reject certain teaching methods at their choosing and not feel forced to conform to them by the inspectorate.”

The insistence of inspectors to see a particular way of teaching was forcing schools to put on “jazzy” lessons just for an Ofsted inspection.

In his foreword, Civitas director David Green said the continued existence of a “quality of teaching” category was “undermining” government policy to move towards more school-based training.

“A school cannot provide teacher training unless it is graded ‘outstanding’ for the quality of its teaching by Ofsted. But, as Peal’s study shows, grades are often arbitrary and based on the personal prejudices of individual inspectors, many of whom remain attached to the discredited misnamed ‘progressive’ methods of the 1960s,” Mr Green writes.

The report is just the latest in a line of studies to come out criticising the inspectorate, which is facing attacks from both unions and education reformers.

The watchdog dismissed Civitas’ report, claiming it did not have a preferred teaching style.

A spokesperson added: “The arguments put forward in this report are largely reheated ones. Our judgements on teaching are predicated on whether children are learning, progressing and achieving good outcomes.

“Since its inception, Ofsted has always come under intense scrutiny and criticism because of the role we play. We will not be swayed from making tough judgements that lead to better outcomes for children.

“Ofsted’s inspections of schools will be brought in-house from September 2015. This will give us more direct control over the selection and training of additional inspectors, and more control over quality assurance.”