I always hear that they represent only a small percentage of cases, or are nearly insignificant compared to the real ones...

For example.. http://www.buzzfeed.com/charlesclymer/5-things-more-likely-to-happen-to-you-than-being-f-fmeu

http://www.vice.com/read/damaging-myths-surrounding-rape-allegations-might-stop-victims-coming-forward