College rape overestimated?

LiJia mentioned Heather MacDonald's piece about the fact that college rape statistics are over-estimated. If anything, they have to be under-reported. But one of the questions that came up for me was the fact that MacDonald cited a 1980 study and blamed this over-estimate on the survey questions. Do you think such a study should be done since it has been 20 years, and my belief is that we would find many more cases of rape in college than a study 20 years ago. But then again, I'm sure Ms. MacDonald would find another argument to blame those "drunken college girls" who do this to themselves.