Measuring fatigue in people with Multiple Sclerosis

Objective: To compare methods of assessing fatigue. Design: Cross sectional. Setting: Community. Subjects: Forty Multile Sclerosis (MS) patients and 20 healthy controls. Main outcome measures: Fatigue questionnaires, SDSA dot cancellation test, finger tapping test, TEA Lottery. Results: The MS patients had significantly higher levels of fatigue than the controls on the Task Induced Fatigue Scale, Fatigue Severity Scale and Fatigue Impact Scale. The Task Induced Fatigue Scale completed whilst imagining oneself driving and the Fatigue Assessment Instrument did not differentiate between MS patients and controls. Finger tapping differentiated between MS patients and controls but there was no significant difference between MS patients and controls on visual and auditory concentration tests. A factor analysis indicated that questionnaire measures of fatigue were interrelated but independent of objective test performance. Conclusions: Questionnaire measures can be used to assess fatigue in people with MS. The FSS differentiated MS patients from controls and is relatively short. It was therefore recommended for clinical use.