Validity and psychometric characteristics of the psoriatic arthritis quality of life (PSAQoL) questionnaire in the Turkish population

The aim of this study was to translate and culturally validate the Psoriatic Arthritis Quality of Life Questionnaire (PsAQoL) into Turkish and to evaluate its reliability and validity in patients with psoriatic arthritis (PsA). A total of 162 PsA patients diagnosed according to CASPAR criteria were recruited from two rheumatology clinics. The PsAQoL was translated and culturally adapted into Turkish using a standardized forward-backward translation method. Internal consistency was assessed using Cronbach's alpha. Construct validity was evaluated by correlating PsAQoL scores with quality of life (SF-36), functional (HAQ), emotional (HADS), and clinical disease activity indices (DAPSA, BASDAI, DAS28). The Turkish version of the PsAQoL was found to be clear, concise, and well understood by patients. The average time to complete the questionnaire was 3.3 ± 0.9 min. Internal consistency was good (Cronbach's α = 0.930). Strong correlations were found with SF-36 physical (r = - 0.744) and mental components (r = - 0.731), indicating convergent validity. Moderate correlations were observed with HAQ (r = 0.533), VAS pain (r = 0.408), HADS-Anxiety (r = 0.535), and HADS-Depression (r = 0.517), while correlations with unrelated clinical parameters such as age and PASI were weak or insignificant, indicating divergent validity. No floor or ceiling effects were detected, and there were no missing responses. The Turkish version of the PsAQoL is a valid, reliable, and practical tool for assessing disease-specific quality of life in PsA. Its ease of use and psychometric strength support its application in both clinical practice and researchs.