TBI Classifications & Severity

Clinicians may use loss or alteration of consciousness, post-traumatic amnesia, structural imaging, and the Glasgow Coma Scale (GCS) when describing traumatic brain injury severity. Classification systems vary, and diagnosis, causation, treatment, and prognosis require qualified medical evaluation.

The ranges below reflect a common VA/DoD-aligned reference. When criteria fall in different categories, clinicians may use the more severe category and the complete clinical record.

Mild TBI (Concussion)

• Loss of consciousness: 0-30 minutes
• Post-traumatic amnesia: 0-1 day
• GCS score: 13-15

The term "mild" describes the initial severity classification, not a guaranteed recovery course. Symptoms and functional effects require individual evaluation.

Moderate TBI

• Loss of consciousness: More than 30 minutes but less than 24 hours
• Post-traumatic amnesia: More than 1 day but less than 7 days
• GCS score: 9-12

Severe TBI

• Loss of consciousness: More than 24 hours
• Post-traumatic amnesia: More than 7 days
• GCS score: 3-8

Possible outcomes and care needs vary. Prognosis and any future-care recommendation should come from qualified providers using the full clinical record.