Most universities in the United Kingdom are breaking equal pay laws, according to university and college lecturers' union Natfhe.
The union's analysis of figures from the Higher Education Statistics Agency shows that female academics in the UK are paid up to Pounds 8,000 less than men doing the same jobs in the same subjects.
It says this confirms that most universities are breaking laws on equal pay for work of equal value.
The figures, which relate to 1997-98, coincide with Hesa figures for 1998-99, published in The THES today, which show that only 9.8 per cent of professors are female - a rise of just 0.6 of a percentage point over the previous year.
Although The THES figures show big differences in the number of women in senior positions in the sector, discrimination appears to exist at all grades and in nearly all subject areas.
Natfhe found that a higher proportion of female staff teaching a subject seems to depress the average salary. Subjects in which women made up about 10 per cent of lecturers - such as mechanical engineering, electrical, electronic and computer engineering and mineral and materials engineering, physics and chemistry - had an overall average salary of Pounds ,064 in 1997-98. In contrast, subjects in which women made up about 30 per cent of lecturers - such as computer networks, nursing and paramedical studies, language-based studies and health and community studies - had an average salary of Pounds 24,914. This is an 8 per cent difference.
Female professors earn more than their male colleagues in only two subject areas, nursing and paramedical studies and architecture, built environment and planning. In anatomy and physiology, they earn Pounds 8,000 less; and in veterinary science, Pounds 7,000 less.
Tom Wilson, head of universities at Natfhe, said the figures would show even greater differences if they included part-time workers because far more women work part-time. He said: "Universities and colleges must act now to monitor all staff and set clear targets for improvement."
Talks between higher education unions and employers on trying to end discrimination are to take place on Monday.
Howard Newby, president of the Committee of Vice-Chancellors and Principals, said: "The CVCP is serious and committed to tackling discrimination as an urgent priority. There are historical and structural reasons for the current situation, but this is no excuse. Insitutional practices must be examined in a serious and committed effort to tackle discrimination."
League table, page 18