A 68-year-old man is brought to the Emergency Department after suddenly developing slurred speech and left-arm weakness while eating lunch.

 He arrived within 25 minutes of symptom onset.

 He is alert, able to follow commands, and has no headache or seizure activity.

Vitals:

 RR 18/min, SpO₂ 97% RA, HR 92 bpm, BP 166/96 mmHg, Temp 36.6°C

 Capillary glucose: 6.2 mmol/L

Examination confirms mild facial asymmetry and reduced left upper-limb power.

 The ambulance crew performed a brief screening tool pre-hospital.

 You now need to establish the diagnosis rapidly inside the ED using a validated assessment tool recommended by NICE.

Which tool is most appropriate to use in the emergency department?