In much of Europe and the UK, everyone must be tested for blind spots in their vision. But in the United States, that’s not the case. And, it turns out, drivers with blind spots are bad news for pedestrians. A recent study found that drivers with blind spots were more likely to hit pedestrians and less able to respond to hazardous situations. Reuters Health reports:

As the drivers travelled at 30 miles per hour (mph) on a city course and 60 mph on a country course, pedestrians appeared about once per minute on each side of the road. Drivers honked the horn to indicate they had seen the pedestrian. People with blind spots were slower to honk the horn compared to people with normal vision, and were slowest when the pedestrian appeared in their blind spot than elsewhere, according to results published in JAMA Ophthalmology.

This isn’t that surprising, since someone with a blind spot, by definition, can’t see the pedestrian that falls in that blind spot. But in the United States these people drive among the rest of us. Vision tests simply measure your overall quality of vision, not specific blind spots. Reuters says that the answer isn’t necessarily barring older drivers from the road:

That doesn’t necessarily mean the U.S. needs more regulations – it means doctors should be able to tell their patients where their particular blind spots are and to be especially careful of obstacles, said Bronstad. “You can have a blind spot in both eyes and still have the acuity to drive,” he said. “If you just have a tiny field loss, you’re not going to have the same result as someone with 20 percent reduced field of vision.”

And there might even be a technological fix:

There are ways to combat these problems with technology, such as talking GPS systems and small lenses mounted on driving glasses, called “bioptic telescopes.” But many older drivers don’t use them, according to a linked editorial by Gordon Legge, head of a lab for low-vision research at the University of Minnesota in Minneapolis.

But until then, consider these drivers just one more really good reason to look both ways before you cross the street.

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