Woken by rumble strips. Reports from drivers who have fallen asleep at the wheel.

Rumble strips are seen as systematic interventions that can help prevent lane-departure accidents. There is little evidence, however, for how or even whether rumble strips intervene to prevent specifically fatigue-related road accidents. We therefore asked drivers who actively recalled falling sleeping behind the wheel about their interactions with rumble strips. Our analyses show that real-world driver experience supports claims that rumble strips act by reducing the severity of the consequences of fatigued driving. Most notably we found that significantly fewer sleep-behind-the-wheel incidents resulted in road departure accidents where rumble strips were present.