Translation and Psychometric Properties of the Persian Version of the Dialysis Symptom Index in Hemodialysis Patients

BACKGROUND Hemodialysis patients have a high physical and psychosocial symptom burden. There is no valid and reliable tool for assessing symptoms of hemodialysis patients in Iran. OBJECTIVES The aim of this study was to determine psychometric properties of the Persian version of the dialysis symptom index (DSI). PATIENTS AND METHODS The forward-backward procedure was applied to translate the DSI from English into Persian (Iranian language). The scale (Persian Version) was tested with a convenience sample of 95 patients with end-stage renal disease referred to main hemodialysis centers from December 2012 to June 2013. Validity was assessed using content, face and convergent validity. To test reliability, the kappa values were calculated for test-retest stability and the Cronbach alpha coefficients were also calculated for internal consistency. RESULTS The mean age of patients was 50.4 (SD = 15.72) years and % 61.1 of patients were male. The most commonly reported symptoms were fatigue, being irritable and nervous. Divergent validity was mostly supported by the pattern of association between DSI and SF-36 (r = -0.18- -0.48, P< 0.05). Cronbach's alpha of the DSI was 0.90 and the weighted kappa ranged from 0.21 to 0.93, and it was greater than 0.4 for 25 of the 30 items. CONCLUSIONS The Iranian version of the DSI had good psychometric properties and can be used to assess symptoms of hemodialysis patients.