The Persian Version of Skindex-29 Health-related Quality of Life Index: Translation and Psychometric Validation

Abstract

Background: Dermatologic diseases have considerable effects on patients’ health-related quality of life (HRQoL). The assessment of diseases’ effects on patients’ lives is an important component of disease management. Although Skindex-29 is one of the most utilized measures for assessing dermatology-specific HRQoL, there is no Persian version of it in Iran. This study aimed to translate Skindex-29 into Persian and assess its psychometric properties. Methods: The study was a methodological study, carried out to examine the psychometric properties and factor structure of the Persian version of Skindex-29. The translation was conducted based on Mapi guidelines. In total, 200 dermatologic patients filled in the dermatology life quality index and the Persian version of Skindex-29. Internal consistency reliability was assessed using Cronbach alpha. Convergent validity and known-group validity were evaluated. Exploratory and confirmatory factor analyses were conducted to test construct validity. Results: The final translated version was comprehensible and Cronbach alpha was 0.967. Skindex-29 total score and its subscales exhibited strong correlations with the dermatology life quality index. Known-group validity was supported by the difference between the mild and severe disease groups (P<0.05). Factor analyses identified three well-fitting factors like the original version, which accounted for 69.95% of the variance of the instrument. Conclusion: This study developed an adequate Persian version of Skindex-29, which can be used as a valid and reliable HRQoL instrument to study Iranian dermatologic patients.