By Angela Harrison
BBC News Online education staff
Students who go to university from state schools usually get better degrees than similar pupils from private schools, a big study suggests.
Ministers want a more diverse intake
Analysis by the body which funds universities for the government found that 18 year olds from state schools and colleges were more likely to get a good degree than similar students, with similar A-level grades, from independent schools.
The Higher Education Funding Council for England (Hefce) carried out the study after previous investigations suggested students from independent schools seemed to do less well than those from state schools.
Researchers wanted to check whether there were other reasons behind the statistics.
They considered - then ruled out - other possible factors.
In particular, they looked at whether it was harder to get a good degree at certain universities which were more popular with students from independent schools.
They looked at whether it was school performance, rather than type of school, which affected a student's achievement in higher education.
"The study took 79,000 18 year olds in England - the whole group which was moving straight from A-levels to higher education in 1997."
The data is from an administrative return rather than a survey.
Hefce's data analysis chief, John Thompson, said: "There can never be complete certainty, but it now seems extremely unlikely that the lower higher education achievement of independent school students can be explained away by some other factor."
The findings will add grist to the mill of the debate over university admissions.
Some argue that pupils from state schools should be given lower offers than those at independent schools.
Bristol University has had to defend itself against accusations of bias against private school pupils because it looks at an applicant's performance relative to others at his or her school.
The government recently set up a task force to check universities have fair admissions policies and are encouraging applications from pupils from poorer families.
The researchers did not aim to pinpoint why students from state schools get better degrees, but looked at theories put forward by other people.
John Thompson said one theory was that children at independent schools might get some extra temporary coaching before exams.
The other, he said, was that once at university, privately-educated children might not work so hard.
John Thompson said: " When we started out we expected performance of the student within the school to be the key.
"A student getting, say, an A and two Bs from a school where that was the best in the year, seemed likely to have more potential than a student from a school where that was below average.
"Contrary to these expectations, we found that the school performance effect was small and inconsistent."
The Independent Schools' Council (ISC), which represents independent schools, says further studies are needed.
A spokesman said: "The research confirms the success of independent schools in enabling their pupils to achieve high A-level results.
"It also confirms that students from independent schools go on to gain a higher proportion of top class degrees than students from other types of schools.
"So far as comparisons of expectations and outcomes are concerned, however, the researchers themselves admit that this is simply work in progress and that other strands of enquiry need to be pursued before firm conclusions can be drawn that might justifiably influence universities¿ selection procedures."