This story has been updated.

More than 20 percent of female undergraduates at the University of Michigan said they were victims of non-consensual sexual behavior within the past year, the school said Wednesday in releasing results of a campus survey on sexual misconduct.

Often, Michigan officials said, victims reported that they were verbally pressured into sexual contact without their consent. The pressure included lies, threats, criticism and expressions of anger after victims said they didn’t want to engage in sexual activity. The unwanted incidents ranged from non-consensual kissing and touching to sexual penetration.

The findings offer an unprecedented window on student experiences at one of the nation’s premier public universities, echoing results of other recent studies of sexual violence among college students. A Washington Post-Kaiser Family Foundation poll of current and recent students nationwide, published June 12, found that 1 in 5 young women say they were sexually assaulted while in college. The Massachusetts Institute of Technology reported last fall that 17 percent of female undergraduates who replied to a survey had experienced unwanted sexual behavior since they enrolled.

Taken together, these and other studies provide powerful evidence of a student culture at colleges and universities in which non-consensual sexual activity is so widespread that it verges on the routine.

The convergence on a victimization estimate of roughly 1 in 5 suggests that researchers are developing an accurate picture of what college women experience, an MIT official said, though questions and methods vary from one survey to another and the nature of the sexual misconduct varies.

“We’re all coming up with the same results,” said Sarah Rankin, coordinator of the institute’s enforcement of the gender-equity law Title IX. “That says something about the validity of that number.”

The challenge now is to get students to report sexual violence. Most who experience it never go to authorities.

Michigan researchers said they were struck by the reasons some victims gave for not reporting unwanted sexual incidents: “It was not a big deal”; “I was not upset”; “I took care of it myself”; and “It was my spouse or partner.”

But Michigan President Mark S. Schlissel said the survey results from his school and others should prompt colleges and society at large to take the issue seriously.

“I’ve heard painful stories from survivors of sexual assault on our campus,” Schlissel said at a news conference in Ann Arbor. “They shared with me what they went through and have asked for my help. So while we are here today to talk about data from our campus climate survey on sexual misconduct, we must not lose sight of the human beings behind the data whose lives have been profoundly affected by sexual misconduct.”

Michigan disclosed results from a survey of a representative sample of its students conducted in January and February. In the past 12 months, the survey found, 11.4 percent said they experienced some form of non-consensual sexual behavior, ranging from touching to penetration. Among undergraduate women, officials said, the share was 22.5 percent.

Among female undergraduates, 11.9 percent said they experienced unwanted oral, vaginal or anal penetration.

Schlissel said he views the problem in personal terms, as a university president, a physician-scientist, an educator and a father. “The issue of sexual misconduct keeps me awake at night,” he said.

To administer the survey, Michigan invited 3,000 randomly selected students to answer questions online. About two-thirds responded. The margin of sampling error for the percentage of undergraduate women who experienced sexual misconduct is plus or minus 3.5 percentage points. For all students, the margin is plus or minus 1.5 points.

The survey results showed several factors are linked to the risk of experiencing unwanted sexual penetration:

  • Women were nearly eight times more at risk than men.
  • Undergraduates were three times more at risk than graduate students.
  • Lesbian, gay or bisexual students were 2.5 times more at risk than heterosexual students.
  • Sorority and fraternity members were 2.5 times more at risk than non-Greek students.
  • Membership in club sports (but not varsity teams) was a risk factor.
  • Under-represented minority students were more at risk.

Michigan, with more than 43,000 students, is a perennial powerhouse in higher education. U.S. News and World Report ranks it among the top five public universities in the nation.

The data reported Wednesday is separate from another study of sexual violence Michigan is conducting with the Association of American Universities. The AAU study, a landmark effort involving hundreds of thousands of students at 27 prominent research universities, is expected to be published as early as September.

In another study, researchers reported in May that 19 percent of female freshmen at an unidentified upstate New York university said they were raped or were victims of attempted rape within a year of starting at school.

Skeptics say the Post-Kaiser poll and other surveys are overstating the problem of sexual assault in college. They point to a 2014 federal Bureau of Justice Statistics report that found female students were less likely to experience rape and sexual assault than non-students. That report found that female students experience sexual assault and rape at an annual rate of 6.1 incidents per 1,000 students.

The methodology of the BJS crime survey differs from the approach used in the Post-Kaiser poll, the AAU survey, the Michigan survey, a federally funded study of the issue in 2007 and others. The crime survey asks directly about rape and sexual attacks; the other studies focus on specific forms of unwanted sexual behavior that students experienced.

Scott Clement contributed to this report.