Validation of French versions of the Facial Disability Index and the Facial Clinimetric Evaluation Scale, specific quality of life scales for peripheral facial palsy patients

OBJECTIVES: To translate and validate French versions of two health-related quality of life questionnaires for patients with peripheral facial palsy: Facial Disability Index (FDI) and Facial Clinimetric Evaluation (FaCE) scale. DESIGN: Prospective cohort study. SETTING: University tertiary referral centre. PARTICIPANTS: A pilot test was performed on 10 subjects (5 patients with facial palsy of more than 1-month duration and 5 normal subjects), and then 67 adult patients with facial palsy were enrolled in the validation study. MAIN OUTCOME MEASURES: Translation of the original questionnaires has followed international guidelines using a forward-backward translation method. A pilot test and a validation study based on the translated questionnaires were performed. Internal consistency, test-retest reliability, validity and responsiveness were assessed. Validity was assessed by comparing to SF-36 and Sunnybrook/House-Brackmann grading systems. Subjects answered scales twice within a one-week interval. RESULTS: Sixty-seven patients were enrolled, among which 63 completed scales one week later (retest). For physical and social functions of FDI and FaCE scores, Cronbach's α representing internal consistency was 0.88, 0.70 and 0.89, and test-retest reliability by intra-class correlation coefficients was 0.81, 0.86 and 0.89, respectively. The correlation of facial movement score of FaCE scale was good with Sunnybrook/House-Brackmann grading systems (0.73 and -0.75, P < 0.01). The correlation of social function of FaCE scale was excellent with social function of SF-36 (0.8, P < 0.01). CONCLUSIONS: French versions of FDI and FaCE scale are psychometrically valid. Both questionnaires can be used for clinical studies to assess the quality of life of patients with peripheral facial palsy.