Eignung der Fahrsimulation zur Beurteilung der Fahrsicherheit bei Tagesschläfrigkeit

The aim of the present project is the development and validation of a test environment in a driving simulator for the assessment of driving ability in patients suffering from daytime sleepiness. A monotonous driving test course was developed that is hard to complete especially for people diagnosed with daytime sleepiness. In order to validate the course, a total of 30 patients suffering from daytime sleepiness caused by sleep apnea and a control group consisting of 10 control subjects drove through this course. Additionally they drove through a test course in real traffic which was designed to match the same criteria as the course in the driving simulation. Before, during and after the trial in the driving simulator, the patients reported significantly more sleepiness than the control group. Descriptive data showed a difference between patients and controls with respect to various driving ability parameters. Thereby, speeding and tailgating were typical driving errors of control subjects while patients tended to driving errors which are associated with sleepiness like bad lane keeping and lane departures. In contrast to this, even descriptively, no difference between patients and control subjects was found in real traffic. An explanation could be that the driving course in real traffic was perceived as an exam situation. Therefore, patients were excited and this excitement masked their sleepiness. Accordingly, patients were not sleepier than the control subjects neither before the drive nor after it. It can be concluded that the driving simulator seems to be better suited to distinguish between patients and control subjects in terms of daytime sleepiness. However, the relevance and implications for driving safety cannot be proven with the available data. It seems that driving in real traffic is very similar to a driving test so that sleepiness is masked by agitation. So it should be scrutinised if driving tests in real traffic are capable of providing the necessary ground truth regarding driving ability of patients suffering from daytime sleepiness.