'Precursory symptoms, awareness or progression of facial palsy' are more useful than 'forehead wrinkling ability' in differentiating central facial palsy examined in the emergency department.

Forehead wrinkling, a traditional CFP sign, is also common in early-stage PFP, decreasing its diagnostic reliability. Patients with solely CFP unable to wrinkle the forehead are very rare at a single institution. Evaluating precursors symptoms, and FP awareness and progression is crucial for differentiation.