U.S. President Barack Obama launches the "It's On Us" campaign to help prevent sexual assault on school campuses while in the East Room at the White House in Washington, September 19, 2014. REUTERS/Larry Downing Advocates of reforming collegiate sexual misconduct policies often cite the "1 in 5" statistic — that roughly 20% of college women will be sexually assaulted during their time on campus.

"One in five of every one of those young women who is dropped off for that first day of school, before they finish school, will be assaulted in her college years," said Vice President Joe Biden said when the White House released a report on sexual assault in April 2014.

Now, a new sexual assault climate survey issued by the Association of American Universities (AAU) may help determine the veracity of the "1 in 5" statistic. Twenty-eight universities including Ivy League schools and large public universities are participating in the AAU survey right now.

The AAU aims to find out how often rape and sexual harassment happens on campus while protecting the privacy of those who participate in the survey, according to the AAU.

That survey could provide a more nuanced picture of rape on campus than the "1 in 5" statistic, which comes from a 2007 survey of two large public universities.

That statistic has been attacked because of the comparatively small number of students surveyed in the original study it's derived from and the researchers' broad definition of "assault." As Glenn Kessler writes in The Washington Post's Fact Check blog, it is "misleading to suggest that it is representative of the experience of all college women."

In a column last week in The Harvard Crimson, several Harvard academics who also helped design the national AAU survey highlight part of the new study's purpose. As they write:

During the last year, we've heard a lot of people critique the one in five number. Many students and faculty have told us that the true prevalence is much lower. Many other students and faculty have told us that the true prevalence is much higher ... This wide range of strongly expressed opinions is facilitated by inconclusive survey evidence. And so we are left with serious questions. Is the true prevalence of sexual assault less than or greater than one in five?

To reliably analyze campus sexual assault and harassment, the Harvard faculty members argue, "we need much more high-quality data, especially surveys in which the vast majority of those invited participate in the survey."

U.S Vice President Joe Biden speaks during an event on protecting students from sexual assault at the Eisenhower Executive Office Building April 29, 2014 in Washington, DC. Win McNamee/Getty Images

In a recent column in The New York Post, Naomi Schaefer Riley — a senior fellow at the Independent Women's Forum — reveals some of the questions Harvard students are being asked in the AAU survey and argues they're too vague and potentially misleading. While many of the questions included in the survey are standard for every university participating, each school has some campus-specific questions.

Here's one of questions Harvard students will reportedly answer: "Since you have been a student at Harvard University has someone had contact with you involving penetration or oral sex without your active, ongoing, voluntary agreement?"

"The 67-part anonymous survey of Harvard students ... seems like it was intended to obscure more than enlighten," Riley writes.

The AAU survey is being administered by the research firm Westat and will be open to students through early May.