ABSTRACT
This chapter is a comprehensive reference manual providing information on the Fatigue Severity Scale (FSS), which is a self-rating scale, described as a fatigue-function measure. The FSS has been used with other neurological groups, including Parkinson’s disease and traumatic brain injury. The FSS shows high internal consistency, good temporal stability, sensitivity to real changes occurring in the patient with a large effect size, and evidence of concurrent and construct validity. The important study by C. M. Pepper et al. provides additional evidence, showing that the FSS can discriminate between the overlapping symptoms of fatigue and depression. A brief history of the instrument's development is provided, along with a description of item content and administration/scoring procedures. Psychometric properties are reviewed and a critical commentary is provided. Key references are cited and in most cases the actual scale is included, giving the reader easy access to the instrument.
