[(Daytime-)Sleepiness at the Wheel: Conceptual Basics for the Evaluation of the Fitness to Drive].

(Daytime-)Sleepiness at the Wheel: Conceptual Basics for the Evaluation of the Fitness to Drive Abstract. The number of accidents that are caused because the driver fell asleep is most likely underestimated. Clear signs of sleepiness are either misinterpreted or ignored. Independent of whether sleepiness is caused by behavior or a medical condition, the short-term and maybe even long-term fitness-to-drive is not given. Despite clear criteria for sleepiness from guidelines, medical reports and practice use a number of paraphrasing and thus misleading terms. To improve clarity in reports and to prepare future research projects, we present our understanding of such terms and suggest a more selective overall use.