The Validity and Reliability of the Persian Version of Kidney Disease Quality of Life Questionnaire-Short Form (KDQOL-SF) in Iranian Patients

Health-related quality of life (HQOL) is greatly impaired in patients with end stage renal disease (ESRD). According to the importance of assessing HQOL in chronic disorders and the need for appropriate and specific instruments in this regard, this study aimed to evaluate the validity and reliability of the Persian version of the kidney disease quality of life questionnaire-short form (KDQOL-SF). The KDQOL-SF questionnaire was translated into Persian with the standard forward-backward translation method. Fifty patients with ESRD under regular hemodialysis filled out the KDQOL-SF questionnaire. Internal consistency was assessed using Cronbach's alpha. Construct validity of the questionnaire was assessed by evaluating the correlation between each dimension's score and the overall score of health using Pearson's correlation coefficient. Cronbach's alpha of the KDQOL-SF was 0.85. Cronbach's alphas of all dimensions of KDQOL-SF were higher than 0.7 except for 4 dimensions of work status (0.60), cognitive function (0.58), quality of social interaction (0.63), and sleep (0.48). Among the kidney disease-relateddimensions, there were significant correlations between the overall health score and symptoms/problems, effect of kidney disease, burden of kidney disease, work status, and dialysis staff encouragement (P < 0.01 to < 0.05). Among SF-36 dimensions, the overall health score was correlated with the physical functioning, bodily pain, mental health, general health perception, and socialfunctioning dimensions scores (P < 0.01 to < 0.05). The Persian version of the KDQOL-SF appears to be an appropriate instrument to assess HQOL in Iranian ESRD patients. Further validation studies to investigate the reliability and validity of the KDQOL-SF after more editions with greater sample size are recommended.