Validation of a French version of the Sunnybrook facial grading system

Background: The aim of this study was to translate the Sunnybrook Facial Grading System and its specific criteria into French and validate its use by French-speaking physicians for facial palsy evaluation.

Material and methods: The original English version of the Sunnybrook Facial Grading System and its specific criteria was translated into French according to international standards. Twenty videos of patients with a wide range of facial palsy in terms of duration and severity were independently rated, twice each, by 6 physicians with varied experience in facial palsy care. Internal consistency and intra- and inter-rater reliability were analyzed.

Results: The French version of Sunnybrook Facial Grading System and its specific criteria both showed good internal consistency, with Cronbach alpha of 0.84 and 0.86 respectively. Inter-rater reliability was excellent in both sessions for the composite score, the score of symmetry at rest and during voluntary movement and synkinesis: intraclass correlation coefficient (ICC) between 0.77 and 0.98. Intra-rater reproducibility on the composite score and subscores was also excellent and comparable for expert, experienced and novice physicians, with an average ICC of 0.95.

Conclusion: The French version of the Sunnybrook Facial Grading System and its specific criteria is reliable, reproducible and easy to use by French-speaking teams for facial palsy evaluation.