The overall objective of the study is to prospectively validate the diagnostic accuracy of the Stroke Mimics Score (SMS). This score is calculated using information collected at the time of the patient's arrival in the Emergency Department (triage) and may assist clinicians in distinguishing between:

1. cerebrovascular events (ischemic stroke, intracerebral hemorrhage, and transient ischemic attack [TIA]),
2. stroke mimics (i.e., conditions that present with stroke-like symptoms but without actual infarction of brain tissue).

In addition, the study aims to compare its results with other existing tools and to evaluate its performance across different patient groups.

Specifically, the present research seeks to generate data on the reliability of the SMS tool in providing an accurate diagnosis.

Inclusion Criteria:

• Age ≥ 18 years at the time of presentation to the Emergency Department.
• Presentation to the Emergency Department with a clinical suspicion of acute stroke, identified at nursing triage and/or through activation of the stroke pathway.
• Presentation to the Emergency Department during the 6-month prospective enrollment period.
• Feasibility of real-time collection of the data required to calculate the Stroke Mimics Score (SMS), including:

age, systolic blood pressure, presence/absence of seizure at onset, presence/absence of headache at onset, presence/absence of confusion at onset, presence/absence of syncope at onset, presence/absence of isolated sensory deficit, presence/absence of motor deficit, history of coronary artery disease, history of prior stroke or transient ischemic attack (TIA).

• Availability of a final hospital discharge diagnosis at the end of hospitalization or Emergency Department observation.
• Signed informed consent from the patient or caregiver. If the patient is unconscious upon arrival at the Emergency Department, deferred consent will be applied.

Exclusion Criteria:

• Age < 18 years.
• Inability to fully collect the data required to calculate the Stroke Mimics Score (SMS).
• Absence of a clearly defined final hospital discharge diagnosis.
• Voluntary discharge, transfer, or death before completion of the diagnostic workup, in the absence of a reliable diagnosis.
• Repeated Emergency Department visits for the same clinical event (only the first visit will be considered).

Adult patients presenting to the Emergency Department with suspected acute stroke during the enrollment period.

The final discharge diagnosis will serve as the gold standard.