The lack of a clear definition of various sexual assault terms within the federal government is making it impossible to determine just how often rape, sexual assault and other gradations of these events are occurring, according to a federal watchdog.

The Government Accountability Office reported Thursday that four federal agencies in particular run at least 10 different programs aimed at collecting data on sexual violence. But GAO said these efforts use 23 different terms to describe these acts of violence, and said the agencies don’t have common definitions for these terms.