Fatigue in Mexican cancer patients and survivors:psychometric properties of the FACIT-Fatigue Scale

Abstract: Background: Fatigue is one of the main symptoms reported by cancer patients and survivors; therefore, valid and reliable assessment is essential. Objective: To evaluate the psychometric properties of the Spanish version of the FACIT-Fatigue Scale in a Mexican sample of cancer patients and survivors, composed predominantly of women diagnosed with breast cancer. Method: A cross-sectional instrumental study was conducted with a convenience sample of 221 participants. Exploratory and confirmatory factor analyses were performed, and internal consistency, composite reliability, and average variance extracted were evaluated. Results: The mean age was 52.1 years (SD = 10.3); 95.9% were women, 84.6% had been diagnosed with breast cancer, and 81.9% were not receiving active treatment. Exploratory factor analysis of the 12 retained items identified two factors, “Subjective Fatigue” and “Functional Impact,” which explained 65% of the variance. After removing An7 and incorporating two residual covariances, the confirmatory model showed good fit indices: χ²(51) = 54.89; CFI = .998; TLI = .997; RMSEA = .019; SRMR = .028; CD = .982. Internal consistency was adequate for the total score (α = .924) and both factors (α = .916 and .820, respectively). Overall, 54.3% of participants fell within the descriptive categories labelled moderate or severe, which were established using quartiles and have not been validated as clinical thresholds. Discussion: The two-factor solution showed adequate fit in this sample, although its development and evaluation using the same participants require independent replication. Conclusion: The findings provide preliminary evidence regarding the internal structure and internal consistency of a 12-item solution of the FACIT-Fatigue Scale in this Mexican sample. This solution should be distinguished from the original 13-item instrument and validated in more heterogeneous samples.