Validity and Reliability of Persian Version of 12-Item Pruritus Severity Score Questionnaire in Patients with Chronic Liver Disease and Pruritus

BACKGROUND Currently, there is no published questionnaire translated in the Persian language for pruritus evaluation in patients with chronic liver disease. Therefore, it would be well worth having a valid and reliable Persian questionnaire for assessing pruritus with its different aspects. This study was designed to evaluate the validity and reliability of the translated version of the 12-Item Pruritus Severity Score (12-PSS) METHODS The patients with pruritus due to chronic liver disease, who referred to the liver clinic affiliated to Tehran University of Medical Sciences, were enrolled in this cross-sectional study. Following the forward-backward translation of 12-PSS into Persian, the content validity index (CVI) and its reliability were assessed. The patients were asked to respond to the visual analog scale (VAS) along with 12-PSS on their visits to evaluate the correlation between them. RESULTS 160 eligible patients were entered in the present study. The mean age was 46.03 (±13.05) years. The Cronbach’s alpha for all domains of 12-PSS was 0.81-0.92 (average 0.89), which showed a strong consistency. The mean VAS and 12-PSS were 5.47±2.55 and 11.71 ± 5.25, respectively, and the correlation of VAS and 12-PSS was strong (p < 0.05, r = 0.89). CONCLUSION The Persian version of 12-PSS is a valid questionnaire for assessing pruritus and follow up response to treatment for patients with chronic liver disease.