Are 20 percent of women sexually assaulted before they graduate college?

The Obama White House is working on ways to reduce sexual assault at the nation’s colleges and universities. In announcing a report of a task force on the problem, Vice President Joe Biden offered this startling statistic:

"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," Biden said.

The stat headlines an initial report from the Task Force to Protect Students From Sexual Assault, which released findings April 29, 2014. President Barack Obama established the task force in January, and echoed Biden’s comments then.

Sexual assault is a serious issue and by most accounts one that continues to put many women, and men, at risk in environments where they should feel safe. Underreporting is a serious problem, and definitive statistics are hard to come by, which is why we’re not rating this on our Truth-O-Meter.

Given that underreporting is a problem, how do officials come up with sound statistics? With that in mind, we thought we’d review Biden’s claim to shed more light on this topic.

The origins of the stat

According to WomensHealth.gov, "sexual assault can be verbal, visual, or anything that forces a person to join in unwanted sexual contact or attention." Offenses range from inappropriate touching to forcible rape.

Biden’s staff said the source of the claim is the Campus Sexual Assault Study conducted for the Justice Department’s National Institute of Justice.

Researchers surveyed undergraduates at two unnamed large public universities (one in the Midwest and one in the South) and received 5,446 Web-based responses from women ages 18 to 25. (If the limitations of a two-school sample jump out at you, you’re not alone, but we’ll get to that in a second.)

The survey found that 1,073 women, or 19.7 percent, reported experiencing an attempted or completed sexual assault since entering college. Researchers noted that "the majority of all sexual assaults involved oral, vaginal, or anal penetration and thus met the legal definition of rape in most states."

You might think at this point that Biden over generalized and lumped sexual assaults together with attempted sexual assaults to reach his figure.

Actually, Biden specified that one in five women report experiencing a sexual assault before graduating. Researchers asked a proportional number of freshmen, sophomores, juniors and seniors whether they had been sexually assaulted at any point while attending college. Therefore, looking at the survey results for just seniors, who could reflect on four or more years on campus, would best address Biden’s focus.

According to data provided by the researchers to the Journal of American College Health, 19.8 percent of seniors reported experiencing a completed sexual assault during college. The figure could actually be higher, they wrote, since the survey was in winter and most students do not complete college until late spring. But one has to wonder if the smaller sample size of just one class could also mean a larger margin of error.

Criticisms of the survey

But let’s go back to the survey methodology for a second.

For starters, the Web-based survey yielded a relatively small response rate of about 42 percent, which the researchers note is lower than other methods, like face-to-face interviews. They hoped, however, that anonymity provided more candid answers and better data.

Additionally, as we noted, only students at two large universities were included in the survey. Experts we spoke with said this is a glaring caveat that makes it difficult to create a national estimate from the results.

"This ‘one in five’ statistic shouldn’t just be taken with a grain of salt but the entire shaker," said James Fox, professor of criminology, law and public policy at Northeastern University.

Large universities may not be representative of experiences at mid-size or small colleges. Further, the two colleges selected may not even be representative of large campuses, Fox said.

Mary Koss, a professor of public health at the University of Arizona, agreed that the Campus Sexual Assault Study "is not the soundest data (the White House) could use."

Fox also noted that many women, 16.4 percent, reported experiencing a sexual assault before entering college, and researchers did not gather evidence on sexual assaults among 18- to 25-year-olds who did not attend college for comparison. So the issue may not be isolated to college campuses, but rather a problem young women in general face, Fox said.

"Without a doubt, sexual assault and date rape are of great concern on college campuses," Fox said. "It should not be dismissed. At the same time, we should be careful not to cite national estimates that are shaky, at best."

Other research

So we’ve poked some holes in the Campus Sexual Assault Study. But what about other research on this topic?

Other surveys asked the question in different ways, and some focused on different definitions of sexual assault. Overall, though, the general trends were relatively consistent with the Campus Sexual Assault Study.

The Medical University of South Carolina released the results of a survey in 2007. Unlike the Campus Sexual Assault Study, the pool of respondents, including 2,000 college women, was national.

The survey found that 11.5 percent of women attending college had been raped, including forcible rape, drug-facilitated rape, and incapacitated rape. That number is relatively on par with the Campus Sexual Assault Survey, which found 3.4 percent of women said they were victims of forced rape and 8.5 percent said they experienced incapacitated rape.

A much earlier survey, the Sexual Victimization of College Women conducted by the U.S. Department of Justice in 1996, concluded that "over the course of a college career — which now lasts an average of 5 years — the percentage of completed or attempted rape victimization among women in higher educational institutions might climb to between one-fifth and one-quarter." That was based on findings that 1 in 36 women experience a completed rape since the start of the school year (the survey was conducted between March and May of 1996).

The survey also found that 15.5 percent of students reported experiencing "sexual victimization," which ranges from rape to unwanted touching. That is in line with the Campus Sexual Assault Study, which found 13.7 percent of women experienced a completed sexual assault.

Koss, who has written extensively on this topic, said the best data comes from a Centers for Disease Control survey, which found that across all age groups, nearly 1 in 5 women are raped in their lifetime and 44.6 percent experience non-rape sexual violence.

If you notice, these are all surveys, and not based on crime statistics. Most surveys have found a much higher prevalence of sexual assaults than the FBI’s uniform crime statistics, which only track what has been reported to police.

All these independent surveys are also much higher than the Bureau of Justice Statistics, which reported in the National Crime Victimization Survey about 350,000 sexual assaults in 2012. To put that in perspective, the Medical University of South Carolina estimated 673,000 rapes among just college women. Critics of the Bureau of Justice Statistics survey say they fail to ask questions that define what rape or sexual assault may include. Researchers have found, for example, that many women do not consider their assault "rape" if they were intoxicated, even though it is largely classified as rape.

Koss broke it down this way: the FBI’s Uniform Crime Statistics equal what gets reported to police, the Justice Department’s National Crime Victimization Survey equals what people disclose to surveyors, and academic research surveys are "what people tell to nongovernmental entities when survey authors have the freedom to phrase the questions as they think best as scholars."

The bottom line

Biden said one in five women are sexually assaulted before they graduate college. Experts we spoke with said that while that statistic is commonly used, the source, a survey of just two colleges, may not be representative of the entire population.

Still, the overall findings in the study were on par with similar surveys conducted over the years that have measured sexual assaults on campus.

Sexual assault is one of the harder issues to quantify. Rapes and other attacks remain underreported and surveys often depend on what questions were asked and who responded. It’s hard enough to determine a national number, let alone one for college students, and that’s something readers should take into account.