Beware Nighttime Drivers

Just because you’ve passed a standard vision test doesn’t mean you can see well enough to drive safely at night. New research from Australia suggests that blurred vision and cataracts can dangerously reduce drivers’ ability to recognize pedestrians on the side of the road. The investigators recruited 28 young adult licensed drivers who had passed the drivers’ vision test and asked them to wear cataract lenses and a simulated refractive blur while driving on a closed road circuit. Their challenge: to detect pedestrians in the glare of simulated headlights. The “pedestrians” wore one of three outfits: all black clothing, all black clothing with a reflective vest or all black with reflectors on their wrists, elbows, ankles, knees, shoulder and waists. The study found that the drivers with simulated cataracts recognized pedestrians only 29.9 percent of the time while those with simulated blurred vision recognized the presence of a pedestrian 52.1 percent of the time. The pedestrians wearing the reflective strips were recognized 82 percent of the time and those wearing all black only 13.5 percent of the time. The study also showed that drivers with normal vision recognized pedestrians at longer distances than the drivers with blurred vision or cataracts.