Shopping carts and kids don't mix.

The shopping carts used in grocery supermarkets and department stores are associated with injuries to more than 25,000 children every year, often severe enough to send them to hospital emergency rooms, according to a national survey. "These are not trivial injuries. They can be life-threatening," points out Gary A. Smith, an assistant professor of pediatrics at Ohio State University and director of emergency medicine at Children's Hospital in Columbus, Ohio.

Smith and his colleagues are calling for a change in the way shopping carts are designed, lowering their center of gravity or widening their wheelbase, and reducing the risk of them tipping over. "Shopping carts were not designed for the safe...