The Cardiff Acne Disability Index (CADI): linguistic and cultural validation in Serbian

Abstract

Purpose: The aims of this study were to translate the Cardiff Acne Disability Index (CADI) into Serbian and to assess its validity and reliability in Serbian acne patients.

Methods: The CADI was translated and linguistically validated into Serbian according to published guidelines. This version of CADI, along with the Serbian version of Children's Dermatology Life Quality Index (CDLQI) and a short demographic questionnaire, was administrated to a cohort of secondary school pupils. The Global Acne Grading Score was used to measure the clinical severity of acne. The internal consistency reliability of the Serbian version of CADI was assessed by Cronbach's alpha coefficient while its concurrent validity was assessed by Spearman's correlation coefficient. Construct validity was examined by factor analysis.

Results: A total of 465 pupils completed questionnaires. Self-reported acne was present in 76% of pupils (353/465). The Serbian version of CADI showed high internal consistency reliability (Cronbach's alpha coefficient = 0.79). The mean item-total correlation coefficient was 0.74 with a range of 0.53-0.81. The concurrent validity of the scale was supported by a moderate but highly significant correlation with the CDLQI (Spearman's rho = 0.66; P < 0.001). Factor analysis revealed the presence of two dimensions underlying the factor structure of the scale.

Conclusions: The Serbian version of the CADI is a reliable, valid, and valuable tool for assessing the impact of acne on the quality of life of Serbian-speaking patients.