More than 23 percent of female undergraduate students said they were victims of sexual assault or unwanted kissing and touching, according to one of the largest surveys on sexual violence at U.S. college campuses.

About 5.4 percent of male undergraduate students had nonconsensual sexual contact, according to the survey of 150,000 students released on Monday. 

The Association of American Universities conducted the survey in April and May on the campuses of 27 universities, including Harvard University, the University of Texas at Austin and the University of Virginia.

The schools emailed the survey to students and got responses from 20 percent of students. The survey notes that those who completed the questionnaire may have been more likely to report being victims of sexual violence.

Nearly 5 percent of students at the University of Kentucky say they were sexually assaulted in the past year, according to a survey of 24,000 students released by the college in August.

One in six female undergraduates at Massachusetts Institute of Technology has been sexually assaulted, according to a survey of more than 10,000 students released in 2014.

Vice President Joe Biden called campus sexual assault an epidemic when the White House launched a task force to address the issue last year.

Last month, New York state launched a specialized police unit to help crack down on sexual assault on college campuses. New York has the largest number of schools being investigated by the U.S. Department of Education for violating federal law in their handling of sexual assault allegations.

According to the survey released Monday, the rates of reporting incidents to campus and law enforcement officials or others were 28 percent or less.

More than half of victims said they did not report incidents because they did not consider it serious enough. Other reasons for not reporting were embarrassment, shame, emotional difficulty, and because they believed nothing would be done.

However, a majority of those surveyed believed a report of sexual assault or misconduct would be taken seriously by campus officials, the survey said.

Rates of sexual assault and misconduct were the highest among undergraduate female students, and those who identify as transgender, non-conforming, questioning, and as something not listed on the survey.

The risk of serious kinds of nonconsensual sexual contact decreases from freshman to senior year, the survey said. A significant number of incidents involve drugs or alcohol, it said.

–Reuters