Accuracy of a Diagnostic Algorithm for the Differential Diagnosis of Vertigo in the ED: the STANDING.

This study evaluate the diagnostic accuracy of a simplified clinical algorithm (STANDING) for the differential diagnosis of acute vertigo in the emergency department. In particular, the investigators want to analyze the sensitivity and specificity of the test for the diagnosis of vertigo of central origin and the reproducibility of the test. In suspected central vertigo of ischemic origin, a duplex sonography to identify vertebral artery pathology will be performed.