Another study confirms that children ages four through eight are safer in booster seats when riding in a car.

In the study, data was collected on children involved in car crashes in 16 states and Washington, DC, between December 1, 1998, and November 30, 2007. Children in belt-positioning booster seats were 45 percent less likely to sustain injuries than similarly aged children in standard vehicle seat belts. Booster seats with and without backs provided similar protection.

Pediatricians should continue to recommend belt-positioning booster seats for children who have outgrown a harness-based child restraint until they are at least 8 years old or 4’9”, according to the study authors. Booster seat laws should cover children through age 8 for the best protective effect, as research has linked passage of these laws with a nearly 40 percent increase in use up to age 8.