Hillary Clinton claimed on the campaign trail in Iowa on Monday that one-in-five women in college have been sexually assaulted, though the ratio she cited has been debunked by many scholars who believe it overstates the problem of campus sexual violence.

“This is a special time and a special place to be talking specifically about an issue that effects one-in-five women on campus,” Clinton said during a “Hillary for Women” event at the University of Northern Iowa.

Clinton’s remarks were timed with the release of a three-pronged policy proposal to help combat the “epidemic” of campus sexual assault. The plan aims to provide a support network for survivors of sexual assault. It also proposes to increase focus on university disciplinary proceedings for accusers and the accused. She also addressed providing sexual violence prevention programs for students earlier in school.

Much of the push for an increased focus on campus sexual violence hinges on the belief that sexual assault is widespread. That 1-in-5 statistic is commonly cited by activists and Democratic politicians to bolster the claim.

Clinton circled back to the stat later in her speech.

“Just look around you,” Clinton urged the audience. “If we were to have one of every five women stand up, that would be a pretty big crowd.”

“It is not enough to condemn campus sexual assault. We need to end campus sexual assault,” she said later.

But the one-in-five number, which President Obama touted in a speech last year, is heavily disputed.

The troubling stat originated with a 2007 study conducted by the National Institute of Justice, a sub-agency of the Justice Department.

The study, which relied on a 15-minute online survey, found that 12.6 percent of students reported that they were the victim of an attempted sexual assault. Another 13.7 percent reported they were the victim of a completed sexual assault. Some students reported being victims of both attempted and completed sexual assaults, bringing the total ratio of victims to 19 percent.

Critics of the study point out that it surveyed students from just two Midwestern universities. The study authors also noted that the study’s “response rates were relatively low,” creating what is known as sample bias. The thinking is that the study was designed in a way that students who have been sexually assaulted would be more likely to participate.

The statistic was cast in further doubt last year when the Department of Justice’s Office of Justice Programs released another study which found a much lower sexual assault rate. Instead of finding a sexual assault rate of nearly 20 percent, the study found that just 6.1 out of 1,000 female students — or 0.61 percent — experienced a sexual assault while attending college.

In addition to that, college students were less likely to be sexually assaulted than their non-college peers. The study found that 7.6 out of 1,000 women in the same 18-24 age range experiences an attempted or completed sexual assault.

“It is something deeply important to me to try to work together, with everybody, to bring about the changes that are necessary in behavior and attitude to try to confront the continuing challenge of violence against women, and in particular here on campuses,” Clinton said Monday.

In addition to Obama’s focus on campus sexual violence, Democratic lawmakers have also increased their focus on the issue — sometimes to an extreme degree.

Last week, Colorado U.S. Rep. Jared Polis asserted during a House Education Committee hearing that all students accused of sexual assault should be expelled from school. He said that even if only 10 percent of the accused are guilty, it’s better to expel all of them just to be on the safe side. (RELATED: Dem Congressman: Expel All Students Accused Of Sexual Assault, Even The Innocent Ones)

“I mean, if there’s 10 people who have been accused, and under a reasonable likelihood standard maybe one or two did it, it seems better to get rid of all 10 people,” Polis said during the hearing.

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