Translation, cross-cultural adaptation, and validation of the Italian version of the Synkinesis Assessment Questionnaire in individuals with peripheral facial palsy.

Abstract

After peripheral facial palsy, the onset of facial synkinesis results in aesthetic disfigurement and local muscle tension or pain, with possible deterioration of patient's well-being and social participation. The availability of valid instruments to evaluate patient-reported severity of facial synkinesis is important to capture the subjective perception of facial impairment. To generate and validate an Italian version of the Synkinesis Assessment Questionnaire, a patient-reported outcome measure to assess patient-perceived severity of facial synkinesis after peripheral facial palsy. Observational study. Outpatient clinic of a Rehabilitation Unit. Seventy-five patients with peripheral facial palsy. Through a process of translation and cross-cultural adaptation, we generated the Italian version of the questionnaire (SAQ-IT) and administered it twice to patients with peripheral facial palsy. We evaluated the clinical severity with the Sunnybrook Facial Grading System (SFGS) and the physical and social/well-being function with the two subscales of the Facial Disability Index (FDI-PHY and FDI-SWB, respectively). Cronbach's alpha was 0.87. Item-total correlations ranged from 0.30 to 0.70, while inter-item correlations ranged from 0.15 to 0.82, with an average value of 0.48. Test-retest reliability showed an Intraclass Correlation Coefficient of 0.946 (95% confidence interval: 0.916-0.966). The minimum detectable change (with a 95% confidence level, MDC<inf>95</inf>) was 13.14 points. The correlation between SAQ-IT and the SFGS synkinesis subscore was rho=0.74, while that with the SFGS composite score was rho=0.25, with the FDI-PHY rho=-0.11 and with the FDI-SWB rho=-0.13. Our study validates the SAQ-IT in Italian-speaking individuals with peripheral facial palsy, confirming its acceptable psychometric properties, and providing the MDC<inf>95</inf>. The availability of a valid instrument for the evaluation of patient-perceived severity of facial synkinesis plays an important role in the definition of tailored rehabilitative interventions after peripheral facial palsy.