“Most of the people who have used our services have actually never filed a police report,” she said, “and that is very common.”

Typical was a call she received three days before Christmas from a woman seeking help for an incident that had happened three months before and had not been reported to police, Fales said.

Fales coordinates her organization’s work on four St. Louis-area campuses, and she has been involved in sexual assault counseling for over a decade, dating to her undergraduate years at Michigan State University. She said she believed the 1-in-5 figure is accurate, and may be even higher.

“I don’t believe that campus sexual violence has decreased in the last 10 years,” she said.

But others say the new BJS data show the campus sexual assault problem has been overstated.

Christina Hoff Sommers, author of the 2000 book, “The War Against Boys: How Misguided Feminism is Harming Our Young Men,” said that one assault was too many but that “on campus it has just been exaggerated” by “hard-line feminists” who believe that “American culture (is) a rape culture.”