John Bald is a former Ofsted inspector and has written two books on the history of writing and spelling. He is Vice President of the Conservative Education Society.

The famous expression, “lies, damned lies, and statistics,” is extended by statistical modelling to take in the future as well as the past, whether to predict it, or, in the case of Ofqual, to dictate it. Those responsible, notably the Chair and Chief Regulator, are statisticians rather than specialists in education. They have educational advice, some of it excellent, but their main interest, as Roger Taylor, its Chair, put it,  is “How do you measure stuff?” When the “stuff” is the standards reached by children in school, and when evidence, such as analysis of the demands of questions in maths exams, or of the language used by candidates in English answers, shows that standards have fallen, there is a clear need to improve the way they are measured, and to apply a brake.

Examination reform has addressed the first part of the problem by cutting out the corruption that had grown up around school-based assessments and coursework. Shortly before its abolition, I had six clear examples in GCSE German alone, including teachers doing the coursework instead of pupils, and a grammar school head who destroyed the integrity of his staff by refusing to accept any grade below a pupil’s target, usually an A. Honest people suffered, and a very senior Ofsted official – not an HMCI – told me it was so widespread that Ofsted could do nothing about it.

The brake is another matter. Before 1993, A level grading was simple. The top five per cent of entrants got an A, for example, and other grades were also decided on percentages of entry, with sample papers kept to ensure comparability between years. A major change in 1993 doubled the proportion of A grades and destroyed the comparison papers, an act of vandalism without parallel in educational record-keeping. It was perhaps no accident that this coincided with the redesignation of polytechnics are universities, setting the scene for Blair’s disastrous target of sending half the population to university at the expense of lifelong debt. Michelle Donelan’s recent comments on this issue are a welcome sign that the tide has turned. Her point that every student with the right grades should be able to obtain the right place is a matter of principle. But what are the right grades, and how do we ensure that students receive them?

Yesterday’s report on A levels shows record numbers of A* and A grades so claims that the government has set out deliberately to penalise schools and teachers are clearly untrue. Donelan pointed out that more candidates got into their first choice of university this year than last.

Nevertheless, schools and candidates cannot be confident about having been graded on their merits. One successful headteacher described the results as “a dog’s dinner”, blaming Ofqual for a statistical straitjacket that did not discriminate between subjects, seriously downgrading the school’s strengths in its specialist areas. It had also ignored a substantial improvement in GCSE results among this year’s candidates, pulling them back on the basis of earlier results. Fortunately, Oxbridge had accepted all but one of the candidates who had received offers, and that case was pending decision.

Ofqual’s failure to discriminate accurately is founded on a misplaced belief in the power of statistical modelling, and a chronic failure in its leadership  to pay sufficient attention to detail when measuring “stuff”. We can expect hard cases to make headlines, and universities to do what they can to mitigate the most obvious injustices. We can also expect an application for Judicial Review.