Their study suggests that at Oxford and Cambridge, A-level grades accurately indicate success and that admissions tutors should not be more lenient towards those from state schools.

Oxford and Cambridge took a smaller proportion of entrants from state schools in 2004 than the previous year, despite government pressure.

The academics, writing in The Oxford Magazine, noted that research published by the Higher Education Funding Council for England in 2003 had shown that, given equal A-level scores, a higher proportion of graduates from state schools achieved a 2:1 than those from the independent sector. Dr N.G. McCrum, Emeritus Fellow of Hertford College, Dr C.L. Brundin and A.H. Halsey, Emeritus Professor of Social and Administrative Studies, said that at Oxford and Cambridge this was not the case. Looking at A-level scores and finals scores of graduates between 1976 and 2002, they concluded that, overall, A-level results determined finals results. “For both types of school for both genders at Oxford and Cambridge, A level dictates finals score, except in the sciences for males,” the dons wrote. “This is surely a boost for the use of A level in the admissions exercise.”

In other words, Oxbridge colleges should not expect state school students to do better than their privately educated peers with the same grades, except if they are male and studying science at Oxford. Conversely, privately educated men studying science at Cambridge also had a lead; traditionally, scientists from private schools have gone to Cambridge.

The academics insist they are making “no comment on the intrinsic value of different institutions and courses”.

Dr Brundin, who taught engineering at Oxford and was Vice-Chancellor of Warwick University, said of the funding council: “We’re saying we can’t challenge their study as a whole, but that we cannot say it applies to a single institution and in particular, it does not apply to Oxbridge.”

The study, which corrected A levels for grade inflation over the decades, showed that a pupil who achieved two A grades and a B grade would continue to do less well in the finals — whatever their background, except as a man studying science — than a student who achieved three A grades.

John Thompson, an analyst for the funding council, argued that the Oxford academics had “not fully appreciated” its findings. “Overall, if you make a comparison, keeping everything the same, state school students do a little better,” he said. At the most selective universities, including Oxbridge, he said, the picture was less clear.

Advocates of widening participation have argued that the findings of the council made the case for tutors being more lenient when admitting comprehensive pupils to the top universities. The latest study appears to favour a system where students are measured entirely on their A-level grades.

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