Arabic version of Skindex-16: Translation and cultural adaptation, with assessment of reliability and validity

Background Quality-of-life is increasingly recognized as an important measure in dermatology; however, most currently available dermatologic quality-of-life measures were originally created for the English language. Skindex-16 being one, is a self-administered questionnaire covering the symptoms, emotions and functioning aspects. Objectives Our aim was to translate into Arabic and culturally adapt Skindex-16 following the international guidelines for cross-cultural adaptation of health-related quality-of-life measures. Moreover, its validity and reliability would be assessed. Methods Translation and transcultural adaptation of Skindex-16 were performed. Subsequently, a cross-sectional study was conducted where 678 persons (338 patients and 340 healthy people) responded to the Arabic version of Skindex-16. Evaluations of the semantic equivalence of back-translated items, reliability, construct validity, and content validity of the Arabic version were the main outcome measures. Results Two problematic items as well as the introductory (header) statement required a second translation and back-translation to achieve satisfactory agreement with the original instrument. The final Arabic version of Skindex-16 was internally reliable (Cronbach's alpha-range for the scales 0.81-0.92). The instrument demonstrated both construct and content validity. As hypothesized, the scores for dermatologic patients were higher than those for healthy persons (mean 31.5 vs. 21.1, P < 0.001, respectively). Similarly, scores for patients with inflammatory dermatosis were higher than those for patients with isolated skin lesions (mean 32.99 vs. 25.3, P < 0.05), indicating a poorer quality-of-life. However, greater than 63% of the patients' responses to an open-ended question about their skin disease were addressed by items in the instrument. Conclusion We have developed a semantically equivalent translation with cultural adaptation of Skindex-16 into Arabic. The assessment of its measurement properties shows that it is quite reliable and a valid measure of the effects of skin diseases on the quality-of-life in Saudi patients.