Students at England’s leading universities were more than twice as likely to experience sexual harassment than those at “lower tariff” institutions, according to analysis.

Data from a national survey of undergraduates shows that 35% of students at “high tariff” universities – those requiring the highest A-level grades for entry – reported experiencing sexual harassment, compared with just over 17% of those at universities requiring the lowest grades for entry and 26% of those at “medium tariff” institutions.

The analysis by the Office for Students, England’s higher education regulator, also uncovered hotspots of sexual harassment and sexual assault or violence against those studying courses requiring high entry grades, such as medicine, dentistry, veterinary sciences or languages.

The OfS said it did not look at the reasons why there was such a large variation between types of institutions: “We observe higher prevalence among students studying at those [institutions] with high tariffs compared with the sector overall … The analysis does not assess the reasons for this variation and should therefore be interpreted with caution.”

The high tariff sector encompasses the Russell Group of research-intensive universities, many of which have medical schools.

Jo Grady, the general secretary of the University and College Union, said: “What is especially alarming about this latest analysis is that it shows sexual harassment is more prevalent at higher tariff institutions, which are deemed more prestigious.

“Perpetrators from these universities are more likely to end up in powerful jobs, risking the reproduction of these toxic cultures. Likewise, it is incredibly worrying that such high levels of sexual harassment were reported in courses like medicine, given this is where the next generation of doctors are being educated.”

Prof Libby Hackett, the chief executive of the Russell Group, said it was “very troubling” to see the scale of sexual harassment and violence reported by students.

“Our universities have zero tolerance for sexual misconduct and work to ensure every student and staff member remains safe on campus,” Hackett said. “Many universities have stepped up these efforts in recent years, with more support and clearer reporting processes – but it’s evident from the data that there is more work to be done.

“We will be working collectively with the regulator, government, charities and wider local communities to understand the risks for the most vulnerable students, respond to students’ needs, and prevent harassment and violence before they occur to make our universities a safer place.”

Amira Campbell, the president of the National Union of Students, said: “I am extremely saddened to see this data that shows just how prevalent sexual misconduct is in higher education … We all need to work together to fight the culture in which sexual harassment and violence thrives.”

Experts who spoke to the Guardian said they had not been able to examine the data in detail since it was released on Friday. But they speculated that high tariff universities were more likely to have students at greater risk of harassment or assault with a higher proportion of young undergraduates living away from home.

The survey found that students attending university away from home said they were more exposed to sexual harassment or sexual assault and violence than those attending a university close to their home or as distance learners.

The initial findings from the survey of 50,000 final-year undergraduates, published last year, reported that one in three female students experienced sexual harassment while nearly one in five women experienced sexual assault or violence during their time as a student.

The latest breakdown also showed that women suffered markedly higher rates of harassment or assault than men in all categories. While 3% of men on architecture, building or planning courses experienced sexual assault or violence, for women the proportion was 20%.

Women with disabilities, including mental health disabilities, also reported attacks at higher rates than their peers or male counterparts.