Psychometric Properties of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) in Chinese Patients Receiving Maintenance Dialysis

Context: Fatigue is a common symptom reported by patients with end-stage renal disease, and it can significantly decrease patients' quality of life. A brief and convenient fatigue assessment tool is needed for Chinese patients on maintenance dialysis.

Objectives: To determine the psychometric characteristics of the Chinese version of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) in patients receiving maintenance dialysis.

Methods: The Chinese version of the FACIT-Fatigue was obtained from the FACIT system. Test-retest reliability of this scale was examined using intraclass correlation coefficients, and the internal consistency was calculated by Cronbach's alpha. Content validity was examined using the content validity index (CVI), scale-level CVI/universal agreement, and scale-level CVI/average agreement. Construct validity was tested using Pearson product-moment correlations of the FACIT-Fatigue scores with the Revised Piper Fatigue Scale, Hospital Anxiety and Depression Scale, Pittsburgh Sleep Quality Index, and disease characteristics during the same period.

Results: A total of 172 patients (111 males and 61 females, mean age 52.6 ± 12.5 years) completed this study, with a median FACIT-Fatigue score of 41 (first and third quartiles 34.3-46). The Chinese version of the FACIT-Fatigue had excellent test-retest reliability (intraclass correlation coefficient = 0.98) and internal consistency (Cronbach's alpha = 0.92); the validity of the scale was supported by CVI, scale-level CVI/universal agreement, and scale-level CVI/average agreement values of at 0.67-1, 0.85, and 0.96, respectively. The standard error of measurement of the FACIT-Fatigue was 1.2. The significant correlations between the FACIT-Fatigue score and the Revised Piper Fatigue Scale (r = -0.658), Hospital Anxiety and Depression Scale (-0.566), and Pittsburgh Sleep Quality Index (-0.489) were supported by the FACIT-Fatigue, with good construct validity (all P < 0.01).

Conclusion: The FACIT-Fatigue had acceptable validity and reliability for maintenance dialysis patients and can be used as a valid tool for the measurement of fatigue among these Chinese patients.