BackgroundSummarizes the frequency, type, and context of sexual assault in a large sample of first-year university women at three Canadian universities.MethodsAs part of a randomized controlled trial assessing the efficacy of a sexual assault resistance education program, baseline data were collected from women between ages of 17 and 24 using computerized surveys. Participants’ experience with sexual victimization since the age of 14 years was assessed using the Sexual Experiences Survey--Short Form Victimization (SES-SFV).ResultsAmong 899 first-year university women (mean age = 18.5 years), 58.7% (95% CI: 55.4%, 62.0%) had experienced one or more forms of victimization since the age of 14 years, 35.0% (95% CI: 31.9%, 38.3%) had experienced at least one completed or attempted rape, and 23.5% (95% CI: 20.7%, 26.4%) had been raped. Among the 211 rape victims, 46.4% (95% CI: 39.7%, 53.2%) had experienced more than one type of assault (oral, vaginal, anal) in a single incident or across multiple incidents. More than three-quarters (79.6%; 95% CI: 74.2%, 85.1%) of the rapes occurred while women were incapacitated by alcohol or drugs. One-third (33.3%) of women had previous self-defence training, but few (4.0%) had previous sexual assault education.ConclusionsFindings from the first large Canadian study of university women since the 1990s indicate that a large proportion of women arrive on campuses with histories of sexual victimization, and they are generally unprepared for the perpetrators they may face during their academic years. There is an urgent need for effective rape prevention programs on university campuses.Trial registrationClinicalTrials.gov NCT01338428. Registered 13 April 2011.