A Multicenter Diagnostic Accuracy Study on Prehospital Stroke Screening Scales

Area of Science:

• Neurology
• Emergency Medicine
• Diagnostic Accuracy Studies

Background:

• Stroke is a leading cause of disability, necessitating rapid diagnosis, especially pre-hospital.
• Effective stroke treatment relies on timely intervention within a critical time window.
• Clinical scales are increasingly used for early stroke detection in pre-hospital settings.

Purpose of the Study:

• To evaluate the diagnostic accuracy of eight pre-hospital clinical stroke scales.
• To compare the sensitivity and specificity of various stroke screening tools.
• To identify the most effective scales for pre-hospital stroke diagnosis.

Main Methods:

• A multicenter diagnostic accuracy study involving 805 patients suspected of stroke.
• Data collected via a checklist including demographics, physical findings, and final diagnosis via brain MRI (gold standard).
• Analysis of 19 physical examination items across 8 distinct clinical scales.

Main Results:

• Accuracy ranged from 63.0% to 84.4%; sensitivity from 71.9% to 95.7%; specificity from 46.5% to 82.8%.
• Medic Prehospital Assessment for Code Stroke (Med PACS) demonstrated the highest sensitivity (approx. 95%).
• Los Angeles Pre-Hospital Stroke Screening (LAPSS) showed the highest specificity (approx. 82.8%) but lowest sensitivity.

Conclusions:

• Cincinnati Prehospital Stroke Scale (CPSS), Face-Arm-Speech-Time (FAST), and Med PACS offer high sensitivity (around 95%) for stroke screening.
• No single scale achieved high specificity (above 95%) across all evaluated cut-offs.
• Further refinement of stroke scales is needed to improve specificity for accurate pre-hospital diagnosis.