Psychometric properties of the Brazilian version of the Sunnybrook Facial Grading System

Abstract Introduction: The Sunnybrook Facial Grading System (SFGS) is a scale to evaluate facial function in three domains, namely resting symmetry, voluntary move-ments, and synkinesis. It is commonly used in scientific research and clinical practice to assess and monitor people with facial paralysis. Objective: To translate and cross-culturally adapt the SFGS, develop a version for the Brazilian population (SFGS - Brazil) and analyze its psychometric properties, including validity, interrater reliability and responsiveness. Methods: A multidisciplinary panel translated and adapted the SFGS into Brazilian Portuguese, creating the SFGS-Brazil version. Next, content validation was carried out by a panel of four physical therapists with clinical experience in caring for people with facial paralysis, in addition to interrater reliability and scale responsiveness after physical therapy intervention. Results: For SFGD validation, committee agreement rate and the content validity index were greater than 90%. Agreement (interrater reliability) was excellent for most items and overall (intraclass correlation coefficient = 0.99; p < 0.000) and the scale proved to be responsive, indicating post-intervention improvement (t = 10.66; p = 0.000). Conclusion: The domains and items of the SFGS-Brazil are conceptually equivalent to those of the original version, and the instrument displays adequate psychometric properties, including validity, agreement and responsiveness. The SFGS-Brazil is suitable for the Brazilian population and can be used in scientific studies and clinical practice.