Cultural adaptation and validation of the Filipino version of Kidney Disease Quality of Life – Short Form (KDQOL‐SF version 1.3)

Abstract

Chronic kidney disease is the 10th leading cause of death among Filipinos. Those with chronic kidney disease are exposed to stressors which effect their daily lives. Therefore, assessment of health-related quality of life is important in these patients. The objective of the present study was to translate the Kidney Disease Quality of Life--Short Form version 1.3 (KDQOL-SF ver. 1.3) into Filipino and measure its validity and reliability. Translation and cultural adaptation began with two translations into Filipino, with reconciliation of the forward translators. Pretesting with 10 renal patients, review by experts (nephrologist, translator and dialysis nurse) and back-translation was also done. The final questionnaire was administered to 80 patients with chronic renal disease undergoing haemodialysis for at least 3 months, who could understand Filipino, and were without life-threatening or terminal conditions at the time of the test. A convenience sample of 30 patients from the group had a repeat test 10-14 days after to determine test-retest reliability. Test-retest reliability was assessed by intraclass correlation coefficient and internal consistency reliability was measured by determining the Cronbach's alpha value. Validity was measured using Pearson's correlation between the overall health rating scale and the items from the questionnaire. All of the items showed good test-retest reliability (intraclass correlation coefficient >0.40), ranging from 0.58 (social interaction) to 0.98 (role--emotional). Internal consistency reliability values were acceptable, with Cronbach's alpha ranging from 0.60 (cognitive function) to 0.80 (physical functioning and role--physical). Regarding construct validity, overall health rating in kidney disease-targeted scales was significantly correlated with symptoms/problems, effects of kidney disease and burden of kidney disease. All items in the SF 36 scales had significant correlation with overall health rating (P < 0.05) except for role--emotional. The Filipino version of the Kidney Disease Quality of Life--Short Form can be used to evaluate the health-related quality of life of Filipinos with chronic renal disease on haemodialysis.