German Instrument for the Assessment of Quality of Life in Skin Diseases (DIELH). Internal consistency, reliability, convergent acid discriminant validity, and responsiveness

Background and Objective. Performance and psychometric testing of the Germa n Instrument for the Assessment of Quality of Life in Skin Diseases (DIELH) . Patients/Methods. The instrument consisting of 36 questions (maximum skore 180, 7 domains) was used in 836 outpatients and quality assessments (validi ty, reliability, responsiveness) were performed. Results. The total skore had a mean of 54 pts. (STD 31,range 0-157) and was normally distributed. Women reported a higher impact on quality of life (m edian 56 vs. 49, p <0.001).ln terms of discriminant validity significant di fferences between diagnostic groups were observed with high scorings for pa tients with eczema, psoriasis, urticaria, and acne (p <0.001). Tests for in ternal consistency (Cronbach's alpha 0.71-0.92) and reliability (r=0.73-0.8 6) revealed valid results. The DIELH correlated well with the DLQI (r=0.78, p <0.001) and moderately with 3 domains of the SF 36 (r=0.25-0.30, p <0.01 ). Changes in the quality of life after 4 weeks were consistent with the co rresponding changes of the skin condition and partially significant. Conclu sions. In the use within a large patient sample the DIELH proved to be feas ible, valid,reliable,and responsive,