NEW YORK (Reuters Health) - More than half of all stroller-related head and face injuries among children one year old and younger occur when children fall out of their strollers, new research shows.

While some of those falls occur when children lean out of or stand in the stroller, some head and face injuries have resulted from falls that took place when the child was simply sitting in the chair, according to a Canadian researcher.

These findings stress the importance of vigilance, even when a child appears securely strapped into a stroller, Steven McFaull of Health Canada in Ottawa told Reuters Health.

"A lot of (these injuries) are just related to supervision," he said. Parents and caretakers may believe a child is sleeping in the stroller, leave them alone for an extended period, "then something like this happens," he said.

A smaller proportion of stroller-related head and face injuries -- 13 percent -- happened when the stroller rolled down stairs or a sleep slope. A smaller percentage of accidents involved a motor vehicle.

The vast majority of the accidents were relatively minor, according to the report, and only four percent of children were admitted to the hospital as a result.

McFaull presented his findings last week during the 80th annual meeting of the Canadian Pediatric Society, held in Calgary.

McFaull obtained his findings from a review of surveys conducted with parents who brought their injured children into one of 15 emergency departments across Canada.

In an interview, the researcher explained that a preliminary look at the data suggests that children tended to receive many of their in stroller injuries when strapped into so-called "umbrella strollers," which are collapsible and tend to be more lightweight and less expensive than other models.

McFaull said that when the stroller is lighter than the child -- as is often the case with the umbrella strollers -- the chair can topple over after simple shifting or leaning, even when the child is sitting and strapped in.

Umbrella strollers tend to be very narrow, he said, and children are often squished in. In that case, when young infants -- who carry much of their weight in their heads -- lean out or get their shoulders out of the stroller, they are in danger of slipping out of the chair or causing it to topple over, he noted.

However, McFaull noted that not all accidents involved umbrella strollers, and children had similar accidents in many other stroller types, such as twin and triplet strollers, standard strollers, and those used for jogging.

Once children became older and more mobile, a larger proportion of falls were due to accidents that occurred when the child maneuvered out of the stroller, McFaull said.

Other tips McFaull offered parents to help avoid these accidents include not leaving the stroller close to stairs -- such as while getting ready to leave the house -- and keeping the wheels locked when not moving.

He described cases where a stroller was knocked over or down an incline when hit by a dog or sibling, accidents that could have been avoided if the wheels had been locked.

A small number of head and face injuries resulted from burns, he said, such as when caretakers using the cup holder on strollers spilled a hot beverage on the child, or when passersby accidentally hit the child with a lit cigarette.

Parents should also avoid attaching a leashed dog to a stroller, McFaull added, for the dog can easily pull the stroller over.