Driving whilst using in-vehicle informationsystems (ivis): benchmarking the impairment tolcohol

Using the Lane Change Task (LCT) a comparison of driving performance was made between normal (baseline) driving, driving whilst using an In-Vehicle Information System (IVIS) and driving while intoxicated at the UK blood alcohol level (80mg per 100ml). An attempt was then made to benchmark LCT performance while using IVIS to a well-established minimal level of acceptable driving performance (i.e. alcohol impaired but legally acceptable), both to provide a safety criterion for LCT performance and to illustrate the effect of IVIS on performance of the driving task. The results provided clear evidence for impaired performance of the LCT when performing an IVIS task in comparison to both baseline (LCT alone) and alcohol conditions [F (5, 15) = 14.421, P<0.05]. However, the LCT was found to be insensitive to the effects of alcohol in the absence of a secondary task. It is concluded that LCT performance can be impaired more when undertaking certain IVIS tasks than by having a blood alcohol level at the UK legal limit but the LCT requires further development before it can be used as a convincing proxy for the driving task. A tentative criterion is offered for minimum acceptable LCT performance when concurrently using an IVIS device based on lateral deviation from the normative model.