The Canadian CT Head Rule (CCHR) only applies to patients with an initial GCS of 13-15, witnessed loss of consciousness (LOC), amnesia to the head injury event, or confusion. The study was only for patients > 16 years of age. Patients were excluded from the study if they had “minor head injuries” that didn’t even meet these criteria. Patients were also excluded if they had signs or symptoms of moderate or severe head injury including GCS < 13, post-traumatic seizure, focal neurologic deficits, or coagulopathy. Other studies have looked at different CDRs for traumatic brain injury including the New Orleans Criteria (NOC). However, CCHR has been found to have superior sensitivity and specificity.