All of the patients in this study received a CT scan to evaluate for brain bleeding or skull fracture and may have had a neurological deficit when they came to the emergency room. While that type of injury can be classified as' mild,' it's a lot more severe than a sport-related concussion typically would be, all in all, I think it's a good study for helping to predict who is at risk for depression and PTSD after a traumatic brain injury sustained in a car accident or from an assault.