Measurement of fatigue in cancer, stroke, and HIV using the Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-F) scale.

OBJECTIVE: Given the importance of fatigue in cancer, stroke and HIV, we sought to assess the measurement properties of a single, well-described fatigue scale in these populations. We hypothesized that the psychometric properties of the Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-F) subscale would be favorable and that the scale could serve as a useful indicator of fatigue in these populations.

METHODS: Patients were eligible for the study if they were outpatients, aged 18 or older, with a diagnosis of cancer (n=297), stroke (n=51), or HIV/AIDS (n=51). All participants were able to understand and speak English. Patients answered study-related questions, including the FACIT-F using a touch-screen laptop, assisted by the research assistant as necessary. Clinical information was abstracted from patients' medical records.

RESULTS: Item-level statistics on the FACIT-F were similar across the groups and internal consistency reliability was uniformly high (α>0.91). Correlations with performance status ratings were statistically significant across the groups (range r=-0.28 to -0.80). Fatigue scores were moderately to highly correlated with general quality of life (range r=0.66-0.80) in patients with cancer, stroke, and HIV. Divergent validity was supported in low correlations with variables not expected to correlate with fatigue.

CONCLUSIONS: Originally developed to assess cancer-related fatigue, the FACIT-F has utility as a measure of fatigue in other populations, such as stroke and HIV. Ongoing research will soon allow for comparison of FACIT-F scores to those obtained using the fatigue measures from the Patient-Reported Outcomes Measurement Information System (PROMIS®; www.nihpromis.org) initiative.