Psychometric Properties of the Fatigue Questionnaire EORTC QLQ-FA12 in a Sample of Female Cancer Patients.

CONTEXT: Cancer patients frequently suffer from fatigue. Recently, the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life group developed a new 12-item fatigue assessment instrument.

OBJECTIVES: The aim of this study was to psychometrically test this questionnaire in comparison with the three-item fatigue scale of the EORTC QLQ-C30.

METHODS: A sample of 354 patients who were being treated for breast cancer or gynecologic cancer were examined using the new fatigue questionnaire EORTC QLQ-FA12 and the EORTC QLQ-C30 during their hospital stay (t1) and three months after hospital discharge (t2). Confirmatory factorial analyses, item analyses, test-retest reliability analyses, and correlation analyses were performed.

RESULTS: The analyses roughly supported the three-factorial structure of the FA12, which comprised the subscales physical, emotional, and cognitive fatigue. The fit indices of the confirmatory factorial analysis were worse than those of the original article but nevertheless acceptable. Cronbach alpha of the total scale was 0.92; the coefficients of the subscales were between 0.79 and 0.93. The correlation between the EORTC QLQ-FA12 total scale and the fatigue scale of the EORTC QLQ-C30 was 0.69 and the correlation between the t1 and t2 scores was 0.45 for the EORTC QLQ-FA12 total scale and between 0.37 and 0.47 for the subscales.

CONCLUSION: The psychometric coefficients justify the calculation of a sum score, which can be used by clinicians to assess the general degree of fatigue. Although the three-item fatigue scale of the EORTC QLQ-C30 stresses the physical aspect of fatigue, the new EORTC QLQ-FA12 covers its emotional and cognitive aspects as well.