The head of the SQA said the exams body did what it was asked to by the Scottish Government and insisted moderation was needed to maintain standards over time.

Fiona Robertson, Chief Examiner, said that the results now being issued will not be able to be compared to past or future results.

She said the SQA was asked to develop a system and said: “The SQA delivered on the Scottish Government’s initial request.”

Ms Robertson appeared before the Scottish Parliament Education Committee the day after John Swinney said all the results downgraded by the SQA would be withdrawn and replaced with the initial teacher estimates.

When asked by Conservative MSP Jamie Greene, if she would apologise like John Swinney and Nicola Sturgeon had done, Ms Robertson said she regretted how some people felt about the process but did not apologise.

She said: "I fully appreciate that, as I highlighted in my opening statement, young people felt that their achievements had been taken outwith their control.

"I absolutely get that and of course I regret how young people have felt about this process."

She said that the identity of schools was not known to those who applied the moderationn which led to 75,000 pupils being downgraded, with more pupils in deprived areas affected than those in more affluent areas.

Instead she explained it was done on the past performance of the schools, without knowing their location.

Iain Gray Labour MSP, asked if the SQA signed off a process knowing that pupils in those schools with a poorer past performance would be more heavily impacted.

While SNP MSP Alex Neil said the SQA refused to listen to previous concerns about the methodology used.

He said: “I think everybody and their granny knew that if you used the record of local schools you'd end up with the situation we ended up with - where the moderation process led to two and a half times the downgrades in the poorest areas than happened in the more affluent areas."