One in five women in college sexually assaulted: the source of this statistic

Article here. Excerpt:

'This statistic is derived from a 2007 study, The Campus Sexual Assault Study, which was conducted for the Justice Department’s National Institute of Justice. The researchers, led by Christopher Krebs of RTI International, also surveyed men, but the statistic cited by the administration focuses on women so we will look carefully at that part of the study.

In the Winter of 2006, researchers used a Web-based survey to interview undergraduates at two large public universities, one in the Midwest and one in the South. A total of 5,446 undergraduate women, between the ages of 18-25, participated as part of a random sample. The survey was anonymous and took about 15 minutes to complete. (Participants received a $10 Amazon.com certificate for participating.)

So, first of all, it’s important to remember that this is a single survey, based on the experiences of students at two universities. As the researchers acknowledged, these results clearly can be generalized to those two large four-year universities, but not necessarily elsewhere. Moreover, the response rate was relatively low:

“Another limitation of the CSA study, inherent with Web-based survey, is that the response rates were relatively low. Although the response rates were not lower than what most Web-based surveys achieve, they are lower than what we typically achieve using a different mode of data collection (e.g. face-to-face interviewing).”

The survey found that 1,073 women, or 19 percent, said that they experienced attempted or completed sexual assault since entering college. The actual breakdown was that 12.6 percent experienced attempted sexual assault and 13.7 percent experienced actual sexual assault. (There was some overlap.)'