In the state of California, some patients who have experienced a traumatic brain injury slip into a coma. The severity of the coma will depend on the specific injury and varies from patient to patient.

Medical professionals utilize the Glasgow Coma Scale to rate the probability of a person’s recovery or lack thereof. A person rated as a 3 has the lowest possible score. A person with a 15 has the highest score and most closely resembles a normal-appearing person.

Research has shown that a person rated at 3 or 4 24-hours after the accident have little chance of recovery. Only 7 percent of these people experience recovery, whole approximately 87 percent will pass away or remain in a vegetative state. Those patients rated from 5 to 7 have a better chance of recovery. In these cases, about half will die or remain in a vegetative state. Persons rated from 8 to 10 have a 68 percent chance of recovery. Those patients rating from 11 to 15 24-hours after the accident have a recovery rate of 87 percent. Recovery rates may include moderate disability or a return to full normal function.

Patients who are above the age of 40 when they experience a coma have a poorer rate of recovery. Those who have remained in a vegetative state for more than a year have very little to no chance of emerging from the coma. Research also shows that a patient who fails to at least open their eyes within 30 days of their injury have a poor prognosis.