Nearly 50 of Ofsted’s most prolific lead inspectors have not judged a single school to be outstanding this year, TES can reveal.

Meanwhile, 106 inspectors who have led at least 10 routine inspections in 2014 have not yet rated any school inadequate, figures show.

One of the 49 lead inspectors not to have awarded a single overall outstanding grade this year has led 36 inspections over the past 11 months - more than any other inspector.

The findings - collated by the Watchsted website and published exclusively by TES - have sparked serious concerns among headteachers about the variability of Ofsted inspections, which they say is causing “fear” in schools across the country.

Stephen Ball, principal of New Charter Academy in Ashton-under-Lyne, Greater Manchester, said the figures suggested “the outcome of an inspection comes down to the luck of the draw”. He added: “It seems to point to real weaknesses in quality assurance in terms of inconsistency between inspection teams.”

An Ofsted spokesman told TES that the body placed “great importance on the accuracy and quality of our Ofsted inspection reports”, and said more than nine out of 10 schools were “satisfied with their inspection outcome”.

Read the full article in the 21 November edition of TES on your tablet or phone or by downloading the TES Reader app for Android or iOS. Or pick it up at all good newsagents.

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