Ofsted has defended a high school inspection which saw two senior inspectors sent in six weeks after the original visit to complete the job.

Five inspectors originally went to Sprowston High on March 10-11, but the inspection was declared 'incomplete', and two senior inspectors returned on April 22.

The final report, published on May 7, judged the school 'requires improvement'.

An Ofsted protocol says incomplete inspections 'very rarely' happen, and are triggered by concerns raised by a school, or by Ofsted's own quality assurance process.

It is not known why this inspection was declared incomplete, and Ofsted largely rejected a freedom of information request about it, but it said it had consulted its legal team over 'the arrangements for finalising and securing the inspection'.

In an email to headteacher Andrew John on April 22, released by the school, Ofsted regional director Andrew Cook apologised for any inconvenience caused by the new visit. Mr John replied: 'There is no need to apologise for the inconvenience this has caused, as we welcome this opportunity.'

Mr Cook told the Evening News: 'Yes, two inspectors went back. We gathered that additional evidence, and it was really important we did so, and in doing so and engaging with the school throughout that process, we came to a final published report at the end of the inspection event which we are completely confident about.

'The whole process of sending inspectors back is not to say we made mistakes necessarily. It's to say actually we just need to make sure that the evidence base is secure.

'Any inspection has to be securely evidence based. I will ensure wherever we are unsure at any level, we will return and make sure that evidence is gathered, because that's the fairest thing for the school.'

Speaking in July, Mr John said: 'The school inspection was deemed incomplete, and then it was deemed complete. That's part of the Ofsted process which they followed.'

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