Conclusion
In general, this study demonstrates that the psychomotor test battery, driving simulator and on-the-road driving tasks, are sensitive to sleep deprivation. However, the lack of apparent correlations between test variables under well-rested and sleep-deprived conditions indicates that each task in this study measures driving impairment differently. This study supports the need for studies in early drug development, including driving tasks as close to real-life driving as possible and indicates the complexity of (impaired) driving behaviour.