The most popular sport to cause cerebral contusions is American football due to the drastic acceleration/deceleration of the brain. If any of these symptoms are felt or noticed, a hospital visit is needed where further machine testing is done. In boxing, the rapid deceleration of the brain after an impact causes the symptoms to progress much faster or at a more traumatic rate. Doctors ringside monitor a boxer's attitude and brain function throughout the fight and are able to stop the match following startling news. Contusions are identified with two forms of diagnosis: acceleration of the brain and direct trauma. A direct trauma injury is much more severe than an acceleration injury (in most cases) and requires much more intensive diagnosis and testing. The full extent of the injury may not be known until testing done in a hospital is complete. In football, medical trainers are well versed to diagnose symptoms pertaining to a traumatic brain injury. They are not, however, able to determine what type of injury it is or the extent the injury stems. Football trainers can medically clear or not clear players based on brain injury symptoms. If a trainer feels that certain symptoms exist that are similar to that of cerebral contusions, they will take the player out of the game and rush them to the hospital. Upon admission into the hospital, a CT scan will be ordered. A CT scan is the quickest method to diagnose cerebral contusions because it can be performed immediately and have fairly exact findings. The best method, as suggested by medical doctors, is an MRI because they present more sensitive and accurate findings. MRI's, however, must be scheduled and cannot be completed immediately following the injury. MRI's also take a long time to perform where the injury a player sustained may get worse within that time frame. "History": The individual is possibly unconscious when examined by medical personnel on the field. A common symptom is prolonged unconsciousness (coma), however this player reports headache, dizziness, nausea, vomiting, and weakness of the extremities (paresis) and makes inappropriate responses to questions. "Physical exam": The individual's level of consciousness is disturbed. A neurological examination may not reveal any localizing signs. The individual with no other serious injuries than cerebral contusion will not have a fractured skull or any signs of opening or penetration of the skull. "Tests": Skull x-rays check for a fracture. CT or MRI detect any bleeding in the skull. The Glasgow Coma Scale classifies the severity of brain injury, with a score of 15 as normal and progressively lower scores indicating greater neurologic injury to the brain.