Students risk being duped into believing government rhetoric that any degree guarantees substantial earnings, a vice-chancellor suggested yesterday.

Deian Hopkin said that estimates of the premium earned by graduates over a lifetime had fallen from £400,000 in 2004 to £100,000.

He indicated that the Government needed to move away from the suggestion that there was an automatic financial benefit. Instead, there should be an emphasis on the advantage of simply improving the mind, he said.

Professor Hopkin, Vice-Chancellor of London South Bank University, is co-chairman of the higher education engagement board at the Department for Children, Schools and Families.

He was speaking at a debate hosted by Policy Exchange, the centre-right think-tank, on a report on graduate employment and earnings published by the 1994 Group, which represents research-intensive universities, including Durham and Exeter.

The report showed that three years after graduating, more than a third of those who studied science or technology subjects at research-intensive universities earned more than £30,000. For those who attended other institutions, the proportion on that salary was less than 14 per cent.

Almost one fifth of arts and social science graduates from the first group of universities were earning more than £30,000, compared with fewer than one in ten from other institutions.

While only 3.4 per cent of science and technology graduates from research-intensive institutions earned less than £15,000, there were four times as many in this category among their counterparts at other universities.

Steve Smith, the Exeter University Vice-Chancellor and 1994 Group chairman, said that the rate of return for doing a degree in Britain was the fourth-highest among OECD countries. He said: “There are differences between which university and which subject, but the rate of return shows it matters more that you actually go to university, rather than which one.”

Professor Hopkin told the debate that the lifetime earnings premium was estimated in 2003 to be about £400,000. Last year Bill Rammell, then the Education Minister, said it was about £100,000.

Professor Hopkin said: “I’ve always been suspicious of rates of return. How can you possibly predict this? There probably will be, in the long term, people who say I came in [to higher education] because of the promise of this money. The £100,000 premium doesn’t take into account tax or national insurance . . . It doesn’t give a hell of a lot more over a lifetime.”

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