A new report from Sen. Claire McCaskill, D-Mo., is shining a light on the growing problem of college sexual assault.

McCaskill, a former sex crimes prosecutor, calls the survey of around 440 schools a "wake-up call," and says the results will lay the groundwork for new bipartisan legislation later this year.

The report highlights several areas of concern related to campus sexual assault, including a widespread failure to investigate reported assault claims.

"More than 40 percent of schools in the national sample have not conducted a single investigation in the past five years," the report says.

At a news conference Wednesday morning, McCaskill said if colleges are claiming assault isn't a problem on their campuses, it's time to think again.

"A university, particularly a large institution that has 10 thousand or more students, if they’re saying they have not had any investigations, that means they are in denial or they are incompetent or they’re not taking this problem seriously," McCaskill said.

The report shows an even more concerning trend at smaller colleges and private institutions, noting, "More than 81 percent of private for-profit schools and 77 percent of schools with fewer than 1,000 students have not conducted any investigations [in the past five years]."

Another problem area is training, or a lack thereof, to equip students and faculty with tools to combat assault.

"More than 20 percent of institutions in the national sample provide no sexual assault response training at all for members of their faculty and staff," the report reads. "More than 30 percent of schools do not provide any sexual assault training for students."

McCaskill expects to have legislation drafted before students head back to school in August or September. For parents concerned about the resources available to their son or daughter on campus, she says it comes down to asking the right questions.

"How many investigations have you had?" she said. "And they should look at how many investigations have occurred in light of the size of the student body, and if that number is low then that should make them pause."