Abstract
This study evaluated and compared the measurement properties of the 13-item Functional Assessment of Chronic Illness Therapy-Fatigue Scale (FACIT-F) and the 9-item Fatigue Severity Scale (FSS) in 118 consecutive Parkinson's disease (PD) patients, using traditional and Rasch measurement methodologies. Both questionnaires exhibited excellent data quality and reliability (coefficient alpha ≥ 0.9), and acceptable rating scale functionality, and both discriminated between fatigued and nonfatigued patients. Factor and Rasch analyses provided general support for unidimensionality of both FACIT-F and FSS, although they do not appear to measure identical aspects of fatigue. No signs of differential item functioning (DIF) were found for the FACIT-F, whereas potential age DIF was detected for two FSS items. These results support the measurement validity of both questionnaires in PD, although the FACIT-F displayed better measurement precision and modest psychometric advantages over the FSS. Availability of psychometrically sound fatigue measures that are applicable across disorders provides a sound basis for advancing the understanding of this common and distressing complaint.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 420-432 |
| Number of pages | 13 |
| Journal | Journal of Pain and Symptom Management |
| Volume | 32 |
| Issue number | 5 |
| DOIs | |
| State | Published - Nov 2006 |
Funding
The study was supported by the Swedish Parkinson Foundation, the Swedish Research Council, the World Federation of Neuroscience Nurses, the Skane County Council Research and Development Foundation, the Vårdal Institute, the Department of Nursing at Lund University, and Inge & Elsa Andersson's Parkinson's Disease Research Foundation.
Keywords
- Fatigue
- Parkinson's disease
- questionnaires
- reliability
- validity
ASJC Scopus subject areas
- Clinical Neurology
- Anesthesiology and Pain Medicine
- General Nursing
