P14 Investigating the different distraction mechanism between cell phone use and conversation with the passenger, through a driving simulator experiment

Abstract

BackgroundDriver distraction is estimated to be an important cause of vehicle accidents. Driver distraction factors can be subdivided into those that occur outside the vehicle and those that occur inside the vehicle. While the factors that occur inside the vehicle seem to have greater effect on driver behaviour and safety, the distraction mechanism is different between each different factor. MethodsThe objective of this research is the investigation of the distraction mechanism between cell phone use and conversation with the passenger. For this purpose, a large driving simulator experiment is carried out, in which 90 drivers from three different age groups (young, middle aged and older) were asked to drive under different types of distraction (no distraction, conversation with passenger, cell phone use) in rural and urban road environment, in low and high traffic.The data collected from the driving simulator experiment include 33 variables including both longitudinal control measures, lateral control measures, the reaction time of the driver at unexpected incidents and other driving performance measures.To achieve the research objectives an appropriate methodology has been developed. Generalized linear mixed models were implemented regarding several performance measures as the data used in this research involve repeated observations from each individual trial (each driver completes six drives in rural and six drives in urban environment). ResultsResults indicate the different distraction mechanism between cell phone use and conversation with the passenger. More specifically, in different driving performance parameters (average speed, speed variability, reaction time) the respective statistical models are differently explained regarding the distraction sources examined. Drivers while talking on the cell phone exhibit what is termed “compensatory behaviour”, because the physical presence of a hand-held phone acts as a reminder to the driver of the potential safety threat posed by the use of the phone. On the other hand while conversing with the passenger, driver has a lower level of compensatory behaviour however his attention is more often diverted from the road. ConclusionsResults clearly suggest that mobile phone use and conversation with the passenger affect in a different way driving performance especially regarding drivers of different age groups. The present research is essential for policy makers, professionals involved in testing safety systems and those involved in designing and evaluating new driving environments.