Translation, cross-cultural adaptation and psychometric validation of the Chinese version of Facial Clinimetric Evaluation Scale (FaCE) and Facial Disability Index (FDI)

Abstract

Purpose: The Facial Clinimetric Evaluation Scale (FaCE) and the Facial Disability Index (FDI) are essential tools for assessing the quality of life (QoL) in patients with peripheral facial palsy (PFP). This study aims to translate, adapt and validate the FaCE and FDI scales to ensure cultural relevance and psychometric validity for Chinese patients with PFP.

Methods: Following the International Society for Pharmacoeconomics and Outcomes Research guidelines, the FaCE and FDI scales were translated and culturally adapted for Chinese use (including forward and back translation). From January to August 2024, 150 Chinese PFP patients and 50 age/gender-matched healthy controls in Sichuan Province were enrolled to evaluate psychometric properties. Statistical analyses included Cronbach's α (internal consistency), two-way random-effects intraclass correlation coefficient (test-retest reliability, 2-week follow-up), exploratory factor analysis (EFA, principal component analysis/varimax rotation, Kaiser-Meyer-Olkin/Bartlett's test; construct validity), Content Validity Index (CVI), Pearson correlations (convergent/discriminant validity VS 36-Item Short Form Health Survey (SF-36)), Mann-Whitney U test (group differences) and standardised response means (SRM)/Cohen's d (responsiveness).

Results: The Cronbach's α for the FaCE scale was 0.835, and for the FDI scale, it was 0.895, indicating good internal consistency. Factor analysis revealed six dimensions for the FaCE scale, while the FDI scale was confirmed to have a two-dimensional structure. Additionally, significant correlations were found between the relevant dimensions of the FaCE and FDI scales and the SF-36, supporting their convergent validity. The Mann-Whitney U test indicated significant differences in initial questionnaire responses between the experimental and control groups (p<0.01). Responsiveness analysis demonstrated that the FaCE scale effectively captured changes in patient status.

Conclusions: This study validates the effectiveness and reliability of the Chinese-version FaCE and FDI in patients with PFP, providing robust evidence for their use as assessment tools for QoL in this population.

Keywords: Healthcare quality improvement; Quality measurement; Surgery.