What does a score of zero on the National Institutes of Health (NIH) Stroke Scale for best language indicate?

NIH Stroke Scale Score of Zero for Best Language (Item 9)

A score of zero on the NIH Stroke Scale for item 9 (Best Language) indicates normal language function with no aphasia. 1, 2

Understanding the NIHSS Language Assessment

• The NIH Stroke Scale is a standardized stroke severity assessment tool with scores ranging from 0 to 42, where higher scores indicate more severe strokes 1
• Item 9 specifically evaluates language function using the following scoring criteria:
  • 0 = Normal language (no aphasia)
  • 1 = Mild to moderate aphasia
  • 2 = Severe aphasia
  • 3 = Mute, global aphasia, or coma 1, 2

Clinical Assessment of Language Function

• The clinical assessment for evaluating language function involves asking the patient to:
  • Describe a standardized picture
  • Name objects
  • Read sentences 2
• A patient scoring 0 on this item demonstrates:
  • Normal conversational fluency
  • Good comprehension
  • Intact naming abilities
  • No significant word-finding difficulties 1, 2
• The patient can produce grammatically correct sentences and follow all commands without difficulty 1

Distinguishing Language from Other Functions

• It's critical to differentiate between language function (item 9) and articulation/dysarthria (item 10) when scoring the NIHSS 3
• A patient may have normal language function (score 0 on item 9) but still have dysarthria (scoring 1 or 2 on item 10) 3
• Similarly, language function should not be confused with level of consciousness (item 1A) - a patient must be sufficiently alert to assess language function accurately 4

Clinical Significance and Implications

• Normal language function (score 0) is a positive prognostic indicator in stroke patients 2
• The absence of aphasia on NIHSS should be interpreted with caution, as research shows NIHSS item 9 has a sensitivity of only 72% for detecting aphasia when compared to comprehensive language assessments 5
• This means some patients with mild aphasia might be misclassified as having normal language function on the NIHSS 5

Common Pitfalls in Assessment

• Do not mistake mild word-finding difficulties for normal language - even subtle hesitations or circumlocutions may indicate mild aphasia (score 1) 2
• Ensure the patient is sufficiently alert for accurate language assessment - decreased consciousness can interfere with language evaluation 4
• Consider cultural and educational factors that might affect language performance 2
• Remember that recovery from aphasia often follows a trajectory, with significant improvements typically occurring in the first two weeks after stroke 6