You've likely heard about the horrifying rates of campus sexual assault, and how one in four female students is sexually assaulted during her time in college. What you may not know is how the problem is compounded according to sexuality.Drawing from surveys of 21,000 students at 21 schools, a new study published in the journal Violence and Gender indicates that bisexual women are more vulnerable to campus sexual assault than any other group of students, with nearly two in five experiencing it. That's compared with one in four gay and bisexual men, similar to the rate of heterosexual women, and one in eight heterosexual men. What's more, involvement in fraternities or sororities was shown to be strongly correlated with the likelihood of experiencing sexual assault."Sexual assault is a very underreported crime for a wide range of reasons, and it is underreported when it occurs on college and university campuses as well," Violence and Gender's editor-in-chief and forensic behavioral specialist Mary Ellen O'Toole, PhD, said in a statement . "To really understand the breadth and depth of this problem, it is critical to understand the victimology of sexual assault, and that it includes all students, not just heterosexual females."