Measurement and prediction of subjective fatigue following traumatic brain injury.

Numerous outcome studies have found fatigue to be a common problem following traumatic brain injury (TBI). This study examined the magnitude, causes and impact of fatigue following TBI using three subjective fatigue scales, and investigated its relationship with demographic and injury-related factors, and mood. Forty-nine controls and 49 TBI participants (36.2% with GCS score of 13-15, 29.8% with GCS score of 9-12, and 34% with GCS score of 3-8) were seen at a mean of approximately 8 months post injury. All participants completed three subjective fatigue measures, including the Fatigue Severity Scale (FSS), Visual Analogue Scale-Fatigue (VAS-F) and Causes of Fatigue Questionnaire (COF). TBI participants reported a significantly greater impact of fatigue on their lifestyle on the FSS relative to controls, and reported activities requiring physical and mental effort as more frequent causes of fatigue on the COF. There were, however, no significant group differences on subscales of the VAS-F. Greater time since injury and higher education levels were associated with higher fatigue levels, independent of the effects of mood. Injury severity and age were not found to be significant predictors of subjective fatigue severity in TBI participants.