Surapon Nochaiwong completed his Doctor of Pharmacy (PharmD) from Chiang Mai  University (CMU), Thailand in 2011. After that, he has held the position of Instructor in Department of Pharmaceutical Care, Faculty of Pharmacy, CMU. His research focuses on clinical areas of pharmacoepidemiologic studies in nephrology including drug safety and effectiveness. He and colleagues formed “The Thai Renal Outcomes Research (THOR) Investigators” in 2015 and received funding from CMU, Health Systems Research Institute of Thailand (HSRI), and National Research Council of Thailand (NRCT). He has published several papers in well-known journals and presented his work in both national and international conferences. 


Dialysis patients with uremic pruritus (UP) have a significantly higher risk of mortality and a poor quality of life. This study aimed to develop and validate a multidimensional scale assessing the UP: Uremic Pruritus in Dialysis Patients (UP-Dial). The development and validation of the UP-Dial instrument was conducted in four phases: (1) Item generation, (2) development of pilot questionnaire, (3) refinement with patient recruitment, and (4) psychometric validation. Participants completed the UP-Dial, the visual analogue scale (VAS) of UP, the Dermatology Life Quality Index (DLQI), the Kidney Disease Quality of Life-36 (KDQOL-36), the Pittsburgh Sleep Quality Index (PSQI), and the Beck Depression Inventory (BDI) during May 15, 2012 to November 30, 2015.  The 27-item pilot UP-Dial was generated with 168 participants. After factor analyses, the final 14-item UP-Dial encompassed three domains: Signs and symptoms, psychosocial, and sleep. Face and content validity were satisfied through the item generation process and review of experts. The psychometric analysis demonstrated that the UP-Dial had good convergent and discriminant validity. The UP-Dial was significantly correlated (Spearman rank correlation, [95% CI]) with the VAS-UP (0.76 [0.69 to 0.83]), DLQI (0.78 [0.71 to 0.85]), KDQOL-36 (-0.86 [-0.91 to -0.81]), PSQI (0.85 [0.80 to 0.89]), and BDI (0.70 [0.61 to 0.79]). The UP-Dial revealed excellent internal consistency (Cronbach’s α 0.90 [0.87 to 0.92]) and reproducibility (intraclass correlation 0.95 [0.90 to 0.98]). The UP-Dial is valid and reliable for assessing UP among dialysis patients. This questionnaire can be used to standardize the effects of intervention in comparative-effectiveness research.