RESUMEN
Chronic renal failure (CRF) is one of a number of major diseases that seriously affects quality-of-life (QOL). In this study, we developed a disease-specific QOL questionnaire in Thai for CRF. A list of items important to QOL of CRF patients was created by interviewing five patients, four nephrologists, and four nephrology nurses to identity items that affect patients’ QOL. Additional items were sought from English questionnaires. Another 50 CRF patients were then interviewed to determine the importance of each item by rating then on a scale of 1 (minimally important) to 5 (extremely important). Patients were also encouraged to add items which were not on the list. For each potential item, a frequency-importance score was calculated by adding each patient’s score. A combination of factor analysis and clinical judgment was then used to develop the final questionnaire, with questions scored on the 5-point Likert scale (ranging from “none of the time” to “all of the time”). Psychometric properties were subsequently evaluated in CRF patients at Siriraj Hospital. The validity of the questionnaire was assessed using the relationship between QOL questionnaire scores and the severity chronic renal failure assessed by the adequacy of dialysis diochemical parameters such as serum albumin, urea and creatinine and nurses’ or patients’ global assessment. Reproducibility and internal consistency were examined twice by interviewing 40 hemodialysis patients who came to hemodialysis clinic and had follow-up one week later. The final questionnaire consisted of 24 questions in five domains (physical symptoms, fatigue, psychological, social and emotional). The scores for all corrected strongly with nurses’ and patients’ assessment scores. The reproducibility of the questionnaire was high (intraclass correlation coefficient between 0.60 and 1.00 for the five domains except for the social domain). A high internal consistency in the questionnaire was found using the o-coefficient of Cronbach (ranging between 0.50-0.86 for the two tests). This questionnaire appears to be valid and reliable for assessing CRF patients.