🧠 NIH Stroke Scale (NIHSS) Test

It's a validated 15-item bedside neurological exam that quantifies stroke severity on a 0–42 scale, originally developed for the NIH tPA stroke trials and now the standard stroke-severity tool used in emergency medicine, neurology, and stroke research worldwide.

Work through all 15 items in order — consciousness, orientation questions, commands, gaze, visual fields, facial movement, arm and leg motor strength (each side separately), limb coordination, sensation, language, speech clarity, and neglect — scoring each from the official criteria as you go, then sum every item for the total. Test the patient's best effort for each item and score what you observe, not what you assume.

A trained rater typically completes the full exam in 5–10 minutes at the bedside, faster with practice and a cooperative patient.

It's a standardised training and testing program — typically completed online through official NIH/American Heart Association-affiliated training platforms — that verifies a clinician can score the NIHSS consistently and accurately. Certification usually involves watching a set of standardized patient examination videos and scoring them correctly against a validated answer key, often required for staff involved in acute stroke care or stroke clinical trials.

These are the different official certification exam sets — each group is a separate collection of standardized patient videos used for initial certification or recertification, so a rater can be retested on a fresh set of cases rather than one they've already seen.

We don't publish answer keys for the official certification videos, and would caution against using ones found online. The certification exists specifically to verify that a rater scores real stroke patients consistently and accurately — using unearned answers defeats that purpose and, since NIHSS scores can influence real treatment decisions, has genuine patient-safety implications. If you're preparing for certification, the most reliable path is reviewing each item's scoring criteria (see the table above), practising with the official training videos, and sitting the real exam on the certifying platform.

A score of 0 means no stroke deficits are detected on this exam. In practice, however, even a 0 doesn't fully exclude stroke — the NIHSS can under-detect posterior circulation and cerebellar strokes — so a normal score should still be interpreted alongside the clinical history and imaging.

It's one input among several. Higher NIHSS scores generally increase the potential benefit of reperfusion therapy in eligible patients, and large-vessel-occlusion thrombectomy protocols often use an NIHSS threshold as part of patient selection — but the actual decision always also depends on time since onset, imaging findings, and contraindications, per local stroke protocol.

The Cincinnati scale (face droop, arm drift, speech) is a fast 3-item prehospital screening tool designed to flag "possible stroke" within seconds. The NIHSS is a detailed 15-item exam performed after arrival, used to grade severity precisely rather than just screen — the two serve different points in the care pathway.

Practice varies by protocol, but serial NIHSS is commonly repeated at fixed intervals in the acute phase (e.g. 24 hours post-thrombolysis) and whenever there's a concern for neurological change, since a rising score is one of the most reliable bedside signs of deterioration.