UW News

April 7, 2003

Parents often mistaken about protecting kids in cars

The mistaken belief that their young children are “too big for a car seat” leads many parents to assume their children are ready to graduate to adult seatbelts. By failing to protect their 4- to 8-year-old children by placing them in booster seats, these parents are leaving young passengers vulnerable to injury and death in motor vehicle crashes, the leading cause of mortality for children in this age group.

Parental reasons for booster seat use and non-use, and the factors influencing these behaviors are the subject of new research at the Harborview Injury Prevention and Research Center and Children’s Hospital and Regional Medical Center. “Too Small for a Seatbelt: Predictors of Booster Seat Use by Child Passengers” is published April 2003 issue of Pediatrics.

Booster seats provide protection for children too small to fit properly in motor vehicle seatbelts, which allow the lap belt to ride up on a child’s abdomen and the shoulder belt to rub against the neck. Booster seats raise children so that the lap and shoulder belts fit correctly. Booster seats are recommended for children who have outgrown their safety seats but who are less than less than 57 inches tall or weigh less than 80 pounds.

Booster seats protect against serious injuries in children better than seatbelts alone. Although 80 percent of younger children were restrained in car seats, when researchers observed almost 3,000 children in cars, they noted only 17 percent between 4- and 8-years-old were properly restrained in booster seats. Observations were conducted in Seattle and Spokane, Wash., and Portland, Ore.

Factors influencing non-use of booster seats include age of the child: For each additional year of age, the likelihood of being properly restrained by a booster seat decreased. A 4-year-old child, for example, was nearly twice as likely to be properly protected as a 6-year-old child, and 8-year-old children almost never used booster seats. A driver’s use of a seatbelt was another key factor, with a strong association between seatbelt use and a child passenger correctly protected by a booster seat.

For parents who did protect their children in booster seats, the most common reason for doing so was “to keep him or her safe.” Other reasons mentioned by these parents included a better fit, a more comfortable seat, and a better view for their children.

A majority of parents who didn’t use booster seats believed that their children were “too big” to require such protection. Other factors included a booster seat that was in another vehicle or at home, not having heard of booster seats, and child resistance.

“We found that many parents still incorrectly believe that children are safe in a seatbelt and have outgrown the need for a booster seat,” says Dr. Beth Ebel, a UW assistant professor of pediatrics and primary author for the study. “These results demonstrate the need for community campaigns to educate parents about booster seat use. Recent enactment of booster seat laws in 15 states, including Washington and Oregon, and the District of Columbia will also help improve booster seat use.”

Dr. Frederick Rivara, a UW professor of pediatrics and adjunct professor of epidemiology, was principal investigator for the study. In addition to Rivara and Ebel, the study was conducted by Dr. Thomas Koepsell, a UW professor of epidemiology, and Elizabeth Bennett, M.P.H., health education manager for Children’s Hospital and Regional Medical Center.