Objectives: To evaluate the reliability and validity of the Apathy Evaluation Scale (AES) and Apathy sub-scale of the Frontal Systems Behavior Scale (FrSBe-A) for people with traumatic brain injury (TBI). To identify an optimal cut-off score indicating presence of apathy according to the AES.
Methods and procedures: A sample of 34 participants with severe TBI currently residing in the community underwent neuropsychological and psychosocial assessment to evaluate reliability, discriminant, convergent and divergent validity. Receiver Operating Characteristic (ROC) curve analysis was undertaken to identify an optimal cut-off score on the AES.
Results: AES and FrSBe-A correlated moderately with each other (r = 0.71). Both AES and FrSBe-A have good internal consistency and discriminant validity with measures of depression and fatigue. Support for hypothesized correlations with similar and dissimilar constructs was not shown. ROC analysis identified a cut-off score of 37 or higher on AES indicated presence of apathy.
Conclusions: AES and FrSBe-A are reliable and valid measures of apathy following TBI. It is suggested that the two scales measure slightly differing aspects of the apathy construct, with AES addressing emotional-affective aspects of apathy more than FrSBe-A, which focuses more heavily on cognitive and behavioral elements of goal-directed behavior.