Rasch analysis of the dermatology life quality index (DLQI) in patients with mild to moderate-severe psoriasis.

Background The Dermatology Life Quality Index (DLQI) is a valuable tool for assessing the quality of life in adult patients with psoriasis. Aims To analyse the reliability and validity of the DLQI to measure the quality of life in patients with mild to moderate-severe psoriasis. Methods This was a secondary validation study nested in a follow-up study.