Many students at the University of Bradford work harder than undergraduates elsewhere to attain their degree, a new report reveals.

The national research shows that choice of subject rather than university dictates how many hours a week students study.

Those reading medicine and dentistry spend more than 35 hours on academic work compared with fewer than 20 hours for students on some other courses.

The average student claimed to spend a total of 25.7 hours either being taught in lectures or seminars or engaged in private study each week, The Higher Education Policy Institute found.

But there were major differences between subjects - with medicine and dentistry students doing ten hours more each week and undergraduates on courses in mass communications five hours fewer.

Students at Bradford University studying subjects allied to medicine, including nursing, midwifery and radiography, put in 31.7 hours of study a week, well above the national average.

They are listed 13th out of 22 universities. Liverpool is top with 42.5 and Sheffield at the bottom with 22.1. However, 68 per cent of Sheffield students still managed 1st or 2.1 degrees against 54.5 per cent at Bradford, in the bottom three of the table.

Bradford students work slightly less than the national average at social studies, putting in 23.7 hours a week but coming a creditable 16th out of 51 on the national list. Students at Cambridge came top with 33.4 hours and the extra hours reaped rewards because 84.5 attained 1st or 2.1 degrees compared with 43.4 at Bradford.

There are 12,000 students at the University of Bradford studying on 140 degree courses at undergraduate level and 80 at post graduate.

The researchers found that at some universities the reality of undergraduate life fell short of expectations. Half of students said that at least some aspects of their university experience were "worse than expected".

Students were most likely to be disappointed with the quality of their academic experiences.

But on a scale of 1-5, Bradford scores 4 for course satisfaction among engineering students and 3.8 for those studying sociology, social policy and anthropology.

University leaders defended the variations between courses and institutions.

Drummond Bone, president of vice-chancellors' group Universities UK, said: "There is no national curriculum in higher education, and so we should not be surprised that different courses at different institutions involve different use of facilities, contact hours and so on."

He said the variation in the distribution of degree classes in different universities "raises some interesting questions".

Sally Hunt, joint general secretary of the University and College Union, representing academics, said: "Students and staff want smaller class sizes. The student-staff ratio is now higher in universities than in our schools."

Minister for Lifelong Learning, Further and Higher Education Bill Rammell said: "Rigorous quality assurance and testing ensures that only those who put in hard work get good degrees."