One in four women in the United States will experience forced intercourse by the time they're 44, and the risk is greater for women who have attended little or no college compared to those who attend four or more years of college.
Women who have attended little or no college are at about 2.5 times greater risk for experiencing forced intercourse. About 8 percent of men report forced intercourse, and men with less than four years of college have four times higher odds of experienced forced intercourse, according to a study by William Axinn, a researcher at the University of Michigan Institute for Social Research and professor of sociology and public policy.
After completing a survey about sexual assault on a college campus, Axinn wanted to study the rate of this kind of assault among people who haven't attended college. To study this, he and his colleagues used data from the U.S. National Survey of Family Growth. The nationally representative survey queries about 5,000 American men and women ages 15-44 annually about their family-related behaviors and outcomes, including whether the respondent has experienced forced intercourse.
The survey focuses on family and reproductive health for both men and women. Some of its questions measure intercourse, including what it terms "forced intercourse." The survey doesn't use the word "rape": according to the National Academy of Science, surveys may undercount sexual assault when they use the word "rape."
"When I first saw how high the rates were on campus, like most Americans, I was deeply disturbed," said Axinn, a research professor in both the Survey Research Center and the Population Studies Center at ISR. "When I thought through the processes and imagined it could be even worse off campus, I was disturbed that we're paying so much attention to the on-campus issue and not giving enough attention to young people who are not fortunate enough to be enrolled in college."
Data from the National Survey of Family Growth tend to be high quality because respondents answer sensitive questions through audio-computer assisted self-interviewing, which provides greater privacy than speaking with an interviewer. These questions include whether a sexual encounter happened during violent assault, intoxication, verbal pressure or verbal degradation.
"Intoxication was a common circumstance for sexual assault, but more common was verbal pressure or verbal abuse," Axinn said. "The parallel between this national result and campus-specific results was striking."
Axinn and fellow researchers Maura Bardos and Brady West, both of the Survey Methodology Program in the Survey Research Center, found that men and women who have the most college experience have the lowest rates of forced intercourse. The reasons are many and hard to quantify, but Axinn thinks it has to do with the resources of college students' parents as well as the benefits of a college environment.
The children of wealthy parents are more likely to go to college, which delays dating, entering into sexual relationships and marriage, Axinn says. On the other hand, people who don't attend college begin dating and having sexual relationships earlier, which increases the risk of sexual assault, Axinn says, pointing out that sexual assault is more likely to be perpetrated by people known to the victim.
College students are also more likely to be supervised.
"Although a campus puts men and women in close physical proximity to each other, it does so in a pretty structured environment: dorm living, supervised classes, libraries. There are people everywhere," Axinn said. "People of the same age who are not enrolled in college may have less supervision in their lives and more opportunity for a relationship to transition into being sexual—which could be lovely, or could be unwanted."
Axinn also stresses that his team's findings are of forced intercourse, which account for less than half of sexual assault, according to previous studies. Other forms of sexual assault that included unwanted touching, kissing or other sexual contact likely drives the 25 percent statistic much higher.
The study was published in the journal Social Science Research.
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William George Axinn et al. General population estimates of the association between college experience and the odds of forced intercourse, Social Science Research (2017). DOI: 10.1016/j.ssresearch.2017.10.006