Patients who present with traumatic injuries are evaluated using the Glasgow Coma Scale. Developed in 1974 by neurosurgeons Graham Teasdale and Bryan Jennett at the University of Glasgow, the scale gives clinicians a standardized way to describe a patient's level of consciousness.
The score measures three responses: eye opening, verbal response, and motor response. The combined score ranges from 3 to 15, with lower numbers indicating more severe impairment of consciousness. A score of 8 or below is commonly associated with severe brain injury, although doctors interpret it alongside the patient's overall condition.
The Glasgow Coma Scale is especially useful because it lets emergency teams track changes over time and communicate quickly between hospitals and specialists. It is not a complete diagnosis: sedation, intoxication, language barriers, facial injuries, or paralysis can affect the result. The Glasgow Outcome Scale is a different tool used later to assess recovery.