Table 1:

Classification of TBI Severity Based on Veteran’s Affairs / Department of Defense Clinical Practice Guideline TBI Criteria and GCS scale

Criteria	Mild*	Moderate	Severe
Structural imaging	Normal	Normal or abnormal	Normal or abnormal
LOC	0–30min	<30 min and <24 hours	>24 hours
AOC / mental state	Up to 24 hours	>24 hours, severity based on other criteria
PTA	0–1 day	>1 day and >7 days	>7 days
GCS (best in first 24 hours)	13–15	9–12	3–8

If a patient meets criteria for more than one category of severity, the higher severity level is assigned. Note: AOC: alteration of consciousness; GCS: Glasgow Coma Scale; LOC: loss of consciousness; PTA: post traumatic amnesia; TBI: traumatic brain injury;

^*Studies assessing individuals with mild TBI were excluded