NIH Stroke Scale (NIHSS)

The National Institutes of Health Stroke Scale (NIHSS) is a 15-item impairment scale used to measure stroke severity.

The original 15-item NIHSS remains the most widely accessible, although several versions have been developed (such as the 5-, 8- and 11-item modified NIHSS) and are available.

• It was originally developed in 19891 and is now the most widely used outcome measure in the recombinant tissue plasminogen activator stroke trials.

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Scoring

NIHSS includes the following domains:

• Level of consciousness
• Eye movements
• Integrity of visual fields
• Facial movements
• Arm and leg muscle strength
• Sensation
• Coordination
• Language, speech and neglect

Each impairment is scored on an ordinal scale ranging from 0 to 2, 0 to 3, or 0 to 4. Item scores are summed to a total score ranging from 0 to 42 (the higher the score, the more severe the stroke).