One in 3 people involved in electric scooter accidents require treatment for injuries at an emergency room, according to a new study by the University of California, Los Angeles, which also found that few riders wear a helmet.

The study appears to be the first to analyze the public health impact of shared electric scooters offered by several fledgling startups, such as Bird and Lime, which are similar to ride-hailing taxi services like Uber and Lyft.

Users in nearly 50 U.S. cities can now rent an electric scooter using each company's app. Rental is inexpensive—Bird, for instance, charges a $1 flat fee plus 15 cents per minute a ride lasts. The scooters can travel at speeds up to 15 mph, and riders typically use them for short trips.

Shortly after the arrival of e-scooters more than a year ago, medical professionals across the U.S. started noticing more and more people coming into emergency rooms with injuries from crashes while riding them. The UCLA researchers had a front-row seat to the action in Los Angeles and Santa Monica, where Bird introduced electric scooters shortly after launching in late 2017.

More on Bike Helmets

To see just how common the injuries were, the researchers examined records on people treated at the UCLA Medical Center, Santa Monica, and Ronald Reagan UCLA Medical Center emergency departments between Sept. 1, 2017 and Aug. 31, 2018. Notably, they found, about one-third of the 249 injured riders covered by the survey arrived by ambulance.

Bird and Lime, two main scooter companies, said that safety is important and they're taking steps to improve it for riders.

Lime, in a statement, pointed to an effort to distribute free helmets to riders and has a dedicated customer support and safety team available to riders 24/7. "Lime supports the [American Medical Association's] recommendations to further innovate helmet designs and for the industry to continue focusing on safety," the statement said. 

Paul Steely White, director of safety policy and advocacy at Bird, said that the company appreciates researchers looking into the safety of e-scooters, but feels the report is "very limited," saying that it "fails to put e-scooter injuries into context as they relate to the high number and severity of injuries and deaths caused by motorcycles and automobiles.”

But the study's authors say that as e-scooters become more popular, it's critical to understand potential risks sooner than later. “There are thousands of riders now using these scooters, so it’s more important than ever to understand their impact on public health,” said Tarak Trivedi, M.D., the study’s lead author, a physician with UCLA, in a statement.

Most Riders Weren't Wearing a Helmet

The study, published Friday in JAMA Network Open, also took note of helmet use among those injured. Just 10 of them, or 4 percent, were wearing a helmet.

The team separately observed electric scooter riders at busy intersections in Los Angeles this past September. In total, they documented 193 people riding scooters. About 94 percent of them were not wearing helmets, the study says.

“Riders, obviously, should be wearing helmets,” says Edward M. Castillo, M.D., at the University of California, San Diego’s Department of Emergency Medicine. Castillo, who was not involved in the current study, says he and his colleagues have documented more than 200 injuries at his hospital stemming from electric-scooter-involved crashes.

But he and other experts CR spoke with acknowledge that using a helmet when riding an electric scooter can be inconvenient, since that would require people to carry a helmet around with them on the off chance they might use one of the devices. 

'Stay Alert'

The UCLA study also examined the types of injuries associated with electric scooter collisions, either when the scooter riders themselves were hurt or pedestrians had been struck. The most common, according to the study, were falls (74 percent), followed by collisions with objects (10 percent), and being struck by a moving vehicle, like a car or bicycle (8 percent). (The vast majority of the injuries—92 percent—were to riders.)

The researchers also looked into the role alcohol played in the crashes. About 5 percent of treated patients had a blood alcohol concentration greater than 0.05 percent, the study says. (California law states that a person with a 0.08 BAC is considered to be driving under the influence.)

Medical experts implored riders not to operate a scooter after a night of drinking, and to follow other commonsense precautions. “Stay alert, don’t ride while wearing headphones, and never ride a scooter if you have been drinking alcohol,” says Vidor Friedman, M.D., president of the American College of Emergency Physicians, in a statement.

The injuries themselves were categorized into three groups: head injuries (40 percent), fractures (32 percent), and cuts, sprains, or bruises without a fracture (28 percent). Fifteen people were admitted to the hospital, including two who were treated in an intensive care unit, according to the study.

Few Rules and Regs

Regulations that exist for e-scooters are scattershot, making it difficult for riders to know at times where to ride. Helmet laws are, mostly, voluntary. A new California law that went into effect this month allows riders over the age of 18 to ride without a helmet. Bird was one of the bill’s main backers.

But experts say that, until more research is conducted on the public health impacts of electric scooters, the safest bet is to ride with a good bike helmet.

“Electric scooters are a promising new transportation option, but safety always must come first,” says William Wallace, a senior policy analyst for Consumer Reports. “And right now, a stunning number of e-scooter users are getting seriously hurt, including with head injuries. Consumers, scooter companies, cities, helmet makers, and safety regulators must work together now to improve the safety of these products.”

Scooter Safety 101

Scooters are an affordable—and fun—means of transportation, but there are some important things you need to know. On the "Consumer 101" TV show, Consumer Reports expert Ryan Felton offers tips for keeping safe while using a scooter.