Comparison of the Box Task combined with a tactile Detection Response Task and the Occlusion Method as measures of secondary task demand

Abstract

In-vehicle information systems (IVIS) demand driver attention and lead to driver distraction and inattention, impairing driving safety. The Box Task (BT) quantifies these secondary task demands concerning visual and manual aspects of the driving task. Combined with the tactile Detection Response Task (tDRT), it also measures cognitive demands. The standard method for assessing secondary task demand is the occlusion method. The present study compares the combined BT+tDRT method concerning various secondary task demands with the standardized occlusion method. In a laboratory study, participants completed artificial and realistic IVIS tasks with BT+tDRT or occlusion. Results revealed that BT+tDRT was able to distinguish different demands of visual, manual, and cognitive tasks, while the occlusion method was only able to distinguish different visual-manual IVIS tasks. Based on the results, we conclude that the combination of BT+tDRT captures the effects of IVIS on driving safety more precisely and comprehensively than does the occlusion method. Future research should compare the findings from this study with data from field studies. Also, the use of BT+tDRT should be further standardized.