Criminologist Lisa Dario set out on a recent study with the assumption that men who had been sexually assaulted would display lower levels of depression than female victims. The hypothesis was based on previous literature: Multiple studies had found that men and women reacted differently to sexual assault, with women tending to display depression and sadness that often turned inward—for example, towards eating disorders or drug use—and men tending to display a tendency towards violence, and even to commit more crimes.

In fact, Dario’s team found no difference between the rates at which men and women who had been sexually assaulted at some point in their lives experienced depression.

“When we began this study, we thought for sure that we would find that females who were sexually assaulted would exhibit higher depression scores than males who were sexually assaulted,” said Dario, assistant professor at the School of Criminology and Criminal Justice at Florida Atlantic University. “I think this is probably because of antiquated ideas that men and women experience emotions differently. What we actually discovered, much to our surprise, is that sexual assault is traumatic regardless of gender.”

Unsurprisingly, victims of sexual assault of both genders reported higher levels of depression than the rest of the population. The May 2017 study, published in the journal Women & Criminal Justice, analyzed data from the National Violence Against Women Survey conducted in 1995-6 for almost 6,000 women and the same number of men.

The assumption that men and women react differently to sexual assault is also due to a gap in research, whereby male victims are “a hidden population,” Dario said. “Unless you’re a juvenile or an inmate, there’s very little research on sexual assault in men.”

Statistics suggest men are assaulted less often than women: One in five women in the US report experiencing rape at some point in their lives, compared to one in 71 men, according to the National Intimate Partner and Sexual Violence Survey.

Dario challenges that assumption. Under-reporting, in both genders, likely means both numbers are higher, she said. She says it’s likely that women are assaulted more often, but that the under-reporting among men may be more extreme because of the stigma associated with coming forward.

Furthermore, the Florida study cites previous research that suggested male sexual assault was systematically underestimated in scientific studies for a number of reasons: More research has been conducted on the effect of sexual assault of women because of an assumption that they’re more often the victims; definitions and categorizations don’t always account for men’s experience; and many population-based sexual victimization studies exclude the prison population, where much male experience occurs.

One 2014 study looked at data from five federal agencies for 2010-12, which included intimate partner violence, crime, and the experience of inmates. It found that as many men as women had had non-consensual sex in the previous 12 months (about 1.27 million in each case.) The researchers also noted that in recent years the percentage of rapes reported in which the victims were men have climbed considerably, likely because of better reporting.

The immediate implications of the Florida study, Dario said, was that support services needed to be made available to men as well as women. “If we’re encouraging men to report more, and we want them to report more, what type of services do we have in place to help them when they do actually report?” Dario asked.