There has been research looking into the effect of night-shift work and car crashes. Huffmyer et al. recently found that anesthesia residents who worked six consecutive night shifts had greater difficulty controlling speed and driving performance in a driving simulator session lasting 55 minutes . Lee et al. reported that night-shift work increases driving drowsiness and degrades driving performance . These factors increase the risk of near-crash driving events. In their study, they found that subjective reports and objective indices of drowsiness became prominent within the first 15 to 30 minutes of driving. They also found that driving for more than 45 minutes after a night shift was likely to increase drowsiness-related impairment .