Dispositional optimism and outcome following traumatic brain injury.

<p><b>OBJECTIVE: </b>Despite vast literature examining the predictors of patient outcome following traumatic brain injury (TBI), the complicated relationship between personality and psychological, cognitive and functional outcomes remains poorly understood. The present study examined the relationship between the personality trait of dispositional optimism (DO) and outcome after moderate and severe TBI in the context of a proposed theoretical model.</p><p><b>METHODS: </b>Forty-five individuals who had sustained moderate-to-severe TBI were recruited through mailings and completed the Symptom Checklist Questionnaire-90 Revised (SCL-90-R), the Telephone Interview for Cognitive Status (TICS), the Craig Handicap Assessment Reporting Technique (CHART) and the Life Orientation Test-Revised (LOT-R). Analyses were conducted to test a model predicting the relationship between personality and patient outcome after TBI.</p><p><b>RESULTS: </b>DO was significantly correlated with psychological distress, but did not predict functional outcome. In addition, two significant mediating relationships were demonstrated: (1) psychological distress was shown to mediate the relationship between dispositional optimism and cognitive ability and (2) cognitive ability mediated the relationship between psychological distress and functional outcome.</p><p><b>CONCLUSION: </b>These findings illustrate that higher levels of DO in individuals sustaining moderate-to-severe TBI are related to better psychological functioning which in turn predicts improved cognitive and functional outcomes.</p>