Science students are most likely to drop out of university, mainly because of poor mathematics, according to the National Audit Office.

In a report published today, the public spending watchdog listed science, technology, maths, engineering and languages as the subjects that had the highest dropout rates in English universities. It said that the retention of science students was the biggest challenge facing universities.

The office’s report said that full-time students with high A-level grades were more likely to complete their degrees than those studying part-time, and that entrants to research-led universities were least likely to quit. Students from poorer backgrounds were also more likely to drop out. Overall, a fifth of full-time students and more than two fifths of part-time students who began their first degree in 2004 were expected to leave their course before it had finished.

The report also said that in an attempt to stop undergraduates becoming fed-up, lectures were being moved increasingly to the afternoon to give students more time in bed. It also stated that universities were repeating courses in the evening to make sure that students who missed earlier lectures and tutorials did not fall behind.

The audit comes a week after the Higher Education Statistics Agency revealed that a third of undergraduates did not finish their studies in some universities in 2005-06, and that the dropout rates were higher than a fifth in more than 30 universities. However, the watchdog found that the real numbers of those quitting had fallen.

St George’s Hospital Medical School and Oxford University had the highest retention rate, at 98.8 per cent and 98.6 per cent respectively, compared with Bolton University, where 81.6 per cent graduated.

The report’s authors said: “When science, technology, engineering and maths students are considered together, they are less likely to continue to a second year of study than students following other subjects,” the study said.

Medical and dentistry students were the most likely to complete their courses. The research will come as a blow to the Government, which is determined to increase the number of home-grown scientists. in the face of increasing numbers from Asia. Angela Hands, one of the report’s authors, said that students with lower grades struggled more with the content of their courses, particularly with maths. “It could become a barrier to more scientists but it’s not a council of despair because a lot of universities are trying to overcome this by putting on extra maths courses,” she said.

Asked whether the quality of maths teaching in schools had deteriorated, she said: “In previous studies we have picked up evidence that maths teaching is not as good as it was.”

The Government said that 77 per cent of 14-year-olds in England reached Level 5 in maths last year, compared with 66 per cent in 1992, and that the numbers taking A-level maths rose by 8 per cent last year.

The audit office study said that retention rates would improve if universities pursued simple strategies such as better support services, early-leaver surveys, remedial maths lessons, bursaries and disability allowances.

Universities UK, the umbrella group of vice-chancellors, said that British universities had one of lowest dropout rates in the industrial world.

Wes Streeting, of the National Union of Students, said that universities’ efforts to take more poor students must be judged on their completion rates. “The completion rate drops most sharply among those institutions that perform best on recruiting students from disadvantaged backgrounds,” he said. “This problem threatens to seriously impede the attempts we are making to raise aspirations and the rate of attainment.”

Times recommends

• Parents face rise in independent school fees
• Crisis in primary school places causes councils to cut back other services
• Labour fails working class on education