APPLICATION OF THE MULTIDIMENSIONAL FATIGUE INVENTORY (MFI-20) IN CANCER-PATIENTS RECEIVING RADIOTHERAPY

In this paper the psychometric properties of the multidimensional fati gue inventory (MFI-20) are established further in cancer patients. The MFI is a 20-item self-report instrument designed to measure fatigue. It covers the following dimensions: general fatigue, physical fatigue, reduced activity, reduced motivation and mental fatigue. The instrume nt was used in a Dutch and Scottish sample of cancer patients receivin g radiotherapy. The dimensional structure was assessed using confirmat ory factor analyses (Lisrel's unweighted least-squares method). The hy pothesised five-factor model appeared to fit the data in both samples (adjusted goodness of it; AGFI: 0.97 and 0.98). Internal consistency o f the separate scales was good in both the Dutch and Scottish samples with Cronbach's alpha coefficients ranging from 0.79 to 0.93. Construc t validity was assessed by correlating the MFI-20 to activities of dai ly living, anxiety and depression. Significant relations were assumed. Convergent validity was investigated by correlating the MFI scales wi th a visual analogue scale measuring fatigue and with a fatigue-scale derived from the Rotterdam Symptom Checklist. Results support the vali dity of the MFI-20. The highly similar results in the Dutch and Scotti sh sample suggest that the portrayal of fatigure using the MFI-20 is q uite robust.