Driving safety after brain injury: Relationships between cognitive and executive functioning, driving behaviour and accident involvement

Abstract

Aims: The objective of this thesis is to investigate whether cognition is related to everyday driving behaviour and accident involvement in a sample of stroke and TBI survivors found fit to drive. More specifically three research aims were investigated: 1) To investigate whether UFOV-score predicts accident involvement; 2) To explore if Sümer’s contextual model applies, and thereby if the relationship between attentional ability and accidents was mediated through aberrant driving behaviour; 3) To investigate if self-perceived executive dysfunction moderate the relationship between attentional ability and aberrant driving behaviour. Methods: The present study is based on a readymade dataset from the Ph.D-project of Per-Ola Rike and Sunnaas Rehabilitation Hospital, which was a prospective one-year follow-up study. The sample was therefore recruited from Sunnaas Rehabilitation Hospital and consisted of 34 TBI and stroke survivors found fit to drive in a multidisciplinary driving assessment. The baseline assessment consisted of The Useful Field of View battery (UFOV) as a measure of cognitive function (attentional ability) and the Behavior Rating Inventory of Executive Function Adult Version (BRIEF-A) as a measure of everyday executive difficulties. At follow-up the participants also completed a Norwegian translation of the Swedish Driver Behaviour Questionnaire (DBQ) to measure post-injury aberrant driving behaviour. Furthermore, post-injury driver characteristics was measured at follow-up by the Sunnaas Driving Pattern Questionnaire (SDPQ). Regression analyses, both linear and logistic, were conducted to explore the predictive relationships between the variables. In addition, a moderator analysis and a mediation analysis was conducted to further explore these relationships. ¨ Main findings/conclusions: Firstly, it was found that a better UFOV3-score predicted a higher risk of being involved in an accident, and it was thereby concluded that UFOV does not seem to be a valid predictor of driving safety among patients with acquired brain injuries. Secondly, everyday executive difficulties (BRIEF-A) moderated the relationship between UFOV3-score and aberrant driving behaviour (DBQ inattention). Thirdly, aberrant driving behaviour (DBQ inattention) mediated the relationship between UFOV3 and accidents, thus confirms Sümer’s contextual model.