The NIH Stroke Scale is an essential clinical tool used to evaluate the degree of neurological impairment in patients who have had or are suspected of having a stroke. This structured assessment helps healthcare professionals measure multiple components of brain function, including cognitive and motor skills, sensory response, speech, and consciousness levels. The total score provides a quantitative measure that guides further management and helps estimate outcomes.

Stroke remains a major public health concern, being one of the top causes of death and long-term disability worldwide. In the United States alone, nearly 800,000 individuals experience a stroke each year. Timely identification and classification of stroke severity are critical for initiating life-saving interventions, such as thrombolytic therapy or endovascular procedures.

The NIHSS was originally developed as part of clinical trials supported by the National Institute of Neurological Disorders and Stroke (NINDS). It has since become widely used in both emergency and inpatient settings. The score typically ranges from 0 to 42, with higher numbers reflecting greater severity. The scale is particularly useful in identifying large vessel occlusions and predicting both short-term and long-term outcomes.

Common conditions where the NIH Stroke Scale is applied include:

• Acute is chemic stroke

• Hemorrhagic stroke

• Stroke mimic conditions such as seizures or migraines

• Transient is chemic attacks (for initial severity estimation)

Clinicians across emergency departments, stroke units, and rehabilitation centers depend on the NIHSS to:

• Guide triage and treatment decisions

• Predict recovery trajectories

• Determine eligibility for clinical trials

Its consistency and evidence-backed scoring structure make it an indispensable part of stroke care pathways.