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According to international sources, the bedside HINTS examination (Head Impulse, Nystagmus, Test of Skew) demonstrates higher sensitivity for detecting acute posterior circulation stroke than early diffusion-weighted MRI (MRI-DWI) during the initial 24–48 hours of an acute vestibular syndrome (AVS). In pooled analyses, early MRI-DWI carries a false-negative rate of approximately 12% to 20% (pooled sensitivity 85.1% [95% CI 79.2–91.0]), as microscopic diffusion restriction in small brainstem or cerebellar infarcts may lag behind physiological neuro-otological dysfunction.

When evaluated in patients with continuous vertigo and nystagmus, bedside HINTS demonstrates an aggregate sensitivity of 94.0% to 95.3% (95% CI 92.5–98.1) and specificity of 86.9% to 92.6% (95% CI 88.6–96.5), as described in international sources. The addition of bedside hearing assessment to create "HINTS Plus" improves sensitivity further (up to 95.7%–99.2%) by capturing anterior inferior cerebellar artery (AICA) territory infarctions that spare the vestibulo-ocular reflex or mimic peripheral lesions.

The diagnostic accuracy of HINTS is strongly operator-dependent in line with international sources. When performed by specialist neuro-otologists or neurologists, sensitivity reaches 94.3%–96.7% and specificity reaches 94.8%–97.6%. In general emergency department cohorts involving non-subspecialists, diagnostic accuracy declines substantially (pooled sensitivity 83% [95% CI 63–95] and specificity 44% [95% CI 36–51]), frequently resulting from testing unselected episodic or positional dizziness rather than true continuous AVS with nystagmus.