Some 3,000 state-school pupils are missing out on their rightful place at elite universities to less-qualified students from the independent sector, according to research published this week.
A report by educational charity the Sutton Trust suggests that thousands of independent-school pupils who go to the UK's 13 leading universities would not be admitted "if higher achieving state school pupils were taking up their fair share of places".
Many of the so-called missing 3,000 state-school pupils apply instead to study at new universities despite having better A-level grades than the entry requirement, according to the trust.
The research found that independent-school pupils who went to a leading university had A-level results that were two grades below those of their state-school counterparts.
The latest research comes as the perennial row over A-level standards was rekindled this week, after a record 22.4 per cent of pupils received A grades, up from 21.6 per cent last year.
Sir Peter Lampl, chairman and founder of the trust, said that lack of aspirations and confidence in their own ability was deterring some state-school pupils from applying to elite institutions.
Family finances and the distance of a university from pupils' home towns also played a role.
Sir Peter said the trust's report revealed that on average, compared with their state-school counterparts, independent-school pupils attended universities that were further from home.
"This is where post-qualification admissions would make a real difference and where an aptitude test, in addition to A levels, would help to identify kids from poorer backgrounds who have ability but who, through no fault of their own, are undertaught in school."
Sir Peter added: "Our leading universities should fairly reflect the ability of the whole population, not just the minority whose parents can afford to send their children to independent schools.
"There are, of course, many excellent and academically demanding courses at other universities, but those who graduate from our leading universities are more likely to have better social networks, better jobs and higher salaries."
The trust found that while 45 per cent of independent-school pupils with an A and two B grades at A level went to an institution ranked among the top 13 in the university league tables, only 26 per cent of state-school pupils with the same grades did so.
While 17 per cent of independent-school pupils entered one of the top 13 universities with the equivalent of one B and two C grades at A level, the same proportion of state-school pupils entered with three B grades.
By contrast, about 10 per cent of state-school pupils with one A and two B grades entered a post-92 university compared with less than 2 per cent of independent-school pupils with the same A-level grades.
A spokesman for the Department for Education and Skills said: "The evidence suggests that admissions are generally fair, but there is an inequality in applying to higher education in the first place.
"Too many students from non-traditional backgrounds lack confidence in their achievements or think that a certain 'type' of university is not for them. We need to tackle these perceptions."
Imbalance of talent