Reliability and validity of the Arabic version of "dermatitis family impact" questionnaire in children with atopic dermatitis.

The aim of this study was to develop an Arabic version of the original English version of Dermatitis Family Impact (DFI) questionnaire and to evaluate its reliability and validity among Saudi families having children with atopic dermatitis (AD). Participants were 379 families of affected pediatric patients with AD diagnosed by consultant dermatologists in addition to a control group of 124 parents, who denied the presence of any dermatologic disorders in their children. To develop an Arabic version of the DFI, rigorous international guidelines for translation-back-translation were followed. In addition, reliability and validity were evaluated by calculating Cronbach's alpha and correlation coefficients. Construct validity was assessed by comparing individual items and total scores among various case severity groups and controls. Cronbach's alpha (=0.90) was acceptable. The inter-item, item-total score and item-severity correlations ranged from moderate to high and were statistically significant (∼0.60, P-values <0.001). The distribution of item responses evaluated by the ceiling and floor effects showed appropriate proportions and a good discrimination between cases and controls and between severity groups. The DFI scale scores (Mean ± SD) were 3.0 ± 1.50 for control, 9.6 ± 2.88 for mild, 14.67 ± 2.27 for moderate and 18.14 ± 2.0 for severe cases (P < 0.001). The results of this study showed that our translated Arabic version of the DFI is an efficient tool in terms of its reliability and validity for the measurement of the disease impact in families with AD.