The research found that over a four-year period, nearly 50,000 people were hurt in accidents involving golf carts.
One of the studies, by the University of Alabama at Birmingham, said about 1,000 Americans are hurt on golf carts every month. Males aged 10 to 19 and people over 80 had the highest injury rates.
A separate study by the Center for Injury Research and Policy at Nationwide Children's Hospital in Columbus, Ohio, said annual injury rates for golf carts increased 130 percent over 16 years ending in 2006. The report said falling or jumping out of carts accounted for the largest number of injuries, 38 percent.
"Part of it is there are more people using them. Part of it is they are using them in more places," said Tracy J. Mehan of the injury research center.
About half of the injuries occurred on golf courses or in other sports venues, such as football stadiums. The rest were on streets or residential property.
Both studies, released Tuesday, reviewed records from U.S. emergency rooms on accidents involving golf carts.
Calls for comment on the studies were not immediately returned by officials of the National Golf Car Manufacturers Association and Augusta, Ga.-based E-Z-GO, which bills itself as the leading manufacturer of golf carts and utility vehicles.
On its Web site, the manufacturers association said there were no recent statistics on golf cart ownership or use. But most of the nation's estimated 16,000 golf courses have at least a few dozen golf carts, and more and more, both gas and battery powered, are being used for transportation in neighborhoods.
UAB researcher Gerald McGwin said some communities encourage the use of golf carts because of their low pollution levels, quiet operation and presumed safety.
"A lot of people perceive golf carts as little more than toys, but our findings suggest they can be quite dangerous, especially when used on public roads," he said in a statement.
McGwin recommends driver education and safety standards for golf carts, which are largely unregulated. He also called for the use of helmets and seat belts and better golf course design to reduce steep hills, sharp curves and other hazards.
The Ohio study suggested a minimum driving age of 16 for golf carts and rules banning children under 6 from riding in them. Driver training programs and written safety policies also could help, it said.
The Ohio report, published in the American Journal of Preventive Medicine, said about 148,000 people have been treated for injuries related to golf carts since 1990.
UAB found there were some 48,255 golf-cart related injuries between 2002 and 2005 alone, or an average of about 1,000 each month.
The numbers of injuries have been increasing as more people rely on golf carts for transportation off golf courses. While there were about 5,772 injuries in 1990, the number more than doubled to 13,411 in 2006.
McGwin said bone fractures and head injuries were among the most common injuries detected in his study, published by the Journal of Trauma: Injury, Infection and Critical Care.
"Golf carts are an attractive transportation solution due to their low emissions and cost effectiveness when compared to traditional motor vehicles," he said. "But more stringent safety standards should be applied to the design and use of golf carts, particularly those operated on public roads."
Golf pro Jim Newton hasn't seen any serious golf cart injuries in the three years since the Ross Bridge Golf Resort and Spa opened in suburban Birmingham. But he said a golfer died on a golf cart while trying to cross a busy highway at a course where he once worked.
Newton worries more about the safety of area residents who ride their own golf carts on busy streets than the golfers on his course.
"Our policy here is supervision. If you monitor it, it greatly reduces your chances of anything happening. We have two monitors on the course at all times," he said. "No one is monitoring on the street."
