Cross-cultural adaptation into French and validation of the SCAR-Q questionnaire.

Abstract

Most questionnaires designed to evaluate patient-reported outcomes regarding scarring are available in English. The objective was to generate a validated French version of the SCAR-Q questionnaire. The SCAR-Q questionnaire (including Appearance, Symptom and Psychological impact scales) was translated into French using a translation-back-translation process in accordance with international guidelines (ISPOR and WHO). For validation, two hundred patients consulting in our tertiary center completed the questionnaire. We tested scale reliability (Cronbach's α), floor/ceiling effects and item redundancy (inter-item correlations). Structural validity was tested using confirmatory factor analysis (CFA) with the robust weighted least squares (WLSMV) estimator and Delta parameterization. Model fit was examined using the root mean square error of approximation (RMSEA), the comparative fit index (CFI) and the Tucker-Lewis index (TLI). Correlations between scales and scale repeatability were tested (Spearman coefficient, Intra-class-coefficient). Four steps were required to obtain a translation consistent with the original version. Two hundred patients completed the questionnaire for validation. Internal consistency analysis found Cronbach's alphas > 0.7 for all scales (0.90 <α< 0.97). No floor or ceiling effect was found for all items (max = 85%). A ceiling effect was observed for all scales. Appearance and psychosocial impact scale items showed redundancy, with many inter-item correlations above 0.7. The CFA of the original structure displayed a reasonable fit, with RMSEA = 0.065, CFI = 0.974 and TLI = 0.972. Scales were positively correlated (0.45 < ρ < 0.65; p < 0.001). Test-retest intra-class correlation coefficients ranged from 0.94 to 0.99 for all scales. A French version of the SCAR-Q questionnaire is validated, ready for use.