Validation of the Japanese Version of the Itch-Related Cognition Questionnaire for Atopic Dermatitis

Abstract

<b>Objectives: </b>To validate the itch-related cognition questionnaire (Kognitive Faktoren beim Juckreiz, KFJ) in Japanese. <b>Patients and Methods: </b>100 patients with atopic dermatitis who received only standard medical treatment participated in the study. The original questionnaire was translated by a German-Japanese bilingual researcher and a native German speaker. Retranslation was made after definitions and fluency had been checked by unaware dermatologists. <b>Results: </b>The Japanese version of the KFJ showed good psychometric qualities similar to the original. This was indicated by the results of factor analysis and internal consistency (catastrophizing scale: α = 0.89; coping scale: α= 0.80). Concurrent validity was supported by state anxiety and depression having a positive correlation only with the catastrophizing scale (r = 0.41 and 0.44 respectively). Supernatural and internal locus of control also had a positive correlation with the catastrophizing scale. Predictive validity was confirmed in that patients with severe skin lesions scored high on the catastrophizing scale. <b>Discussion: </b>These findings support the utility of the Japanese version of the KFJ, which has the advantage of measuring precisely the outcome of psychological interventions focusing on coping with itch in atopic dermatitis patients.