Ofsted inspectors will not look at a school’s internal performance data under the watchdog’s planned new inspection regime because it says it can be unreliable and diverts teachers’ time away from education.

The inspectorate has said that instead it wants its inspectors to get as much first-hand evidence as possible from speaking to teachers and pupils, observing lessons and looking at children’s work.

It is launching a new inspection framework from September which is set to focus on curriculum and the overall quality of education that a school provides and give less weight to exam results and performance measures.

Matthew Purves, Ofsted’s deputy director for schools, said that “data should not be king” during inspections.

In a new video published by Ofsted, he said: “Too often a vast amount of teachers’ time is absorbed into recording, collecting and analysing excessive progress and attainment data within schools. And that diverts their time away from what they came into the profession to do. which is be educators.

“And, in fact, with much of that internal progress and attainment data, they and we can’t be sure that it is valid and reliable information.”

He said Ofsted is proposing that from September inspectors will not look at school’s own attainment and progress data under the new framework.

Ofsted: ‘Data should not be king’

However, it will continue to look at the school’s performance in national tests and exams.

Mr Purves added: “Ofsted’s job on inspection is to focus on what matters for pupils’ education, drawing on a range of evidence. And that will include national performance data. But data is only a starting point, prompting further inspection activity and evidence-gathering.”

Stephen Rollett, the inspection and accountability specialist for the Association of School and College Leaders, tweeted saying Ofsted’s plans to ignore internal data had received a mixed response when presented to ASCL members earlier this year.

Schools data analyst James Pembroke described Ofsted’s plan as a “nuclear option”.

“Essentially, Ofsted have woken up to the fact that much of the data they have come to rely on over the years may well be a pile of fabricated nonsense, and their only option - the nuclear option - is to ignore it,” he wrote in a blog.

He said that although the overwhelming reaction to the plans on social media was positive, he said it will cause concern for some schools.

“Clearly not all schools are happy about this proposal,” Mr Pembroke added. “There are those that have invested heavily in tracking systems and implemented them almost entirely with Ofsted in mind, only to be told that inspectors will ignore it.”

Earlier this year, when outlining plans for the new inspection framework, Ofsted’s chief inspector, Amanda Spielman, warned that teachers were being reduced to data managers.

Commenting on the role of data in future inspections, Mr Purves said: “Outcomes really matter, and the impact of a good curriculum, well-taught, is that pupils will achieve great outcomes. They’ll gain qualifications that they can take into the next stage of life. But in all of this, data should not be the only thing we look at. And data should not be king.”

Last week Ofsted published the findings of research into how it will assess the quality of a school curriculum. It aims to inspect schools on the intent, implementation and impact of a school curriculum.

Its findings show that, in the research, just a quarter of primary schools scored highly for the quality of their curriculum.

Ms Spielman has said that Ofsted is not raising the bar with its new inspection framework and that it does not want to downgrade vast numbers of schools.