Booster seats are designed for use by children aged four to eight years, while travelling in motor vehicles. They aim to raise the child off the vehicle seat so that the adult seat belt fits correctly and the child can travel in greater comfort and safety. Public health and traffic safety agencies recommend the use of booster seats in children until the vehicle seatbelt fits properly; typically when the child is at least 58 inches tall, has a sitting height of 29 inches and weighs about 80 pounds.
In children aged four to seven years, booster seats are estimated to reduce the odds of sustaining clinically significant injuries during a crash by 59%, when compared to using ordinary vehicle seatbelts. Despite the evidence of effectiveness, many children are not restrained in age-appropriate booster seats.
In light of the strong evidence for the safety benefits of booster seats, interventions specifically aimed at promoting their use have been implemented. To evaluate the effectiveness of such interventions, the authors of this systematic review examined all high quality trials investigating their effect on acquisition and use of booster seats.
The authors found five studies involving a total of 3,070 participants. All interventions investigated by the studies were found to increase the use of booster seats, compared to the group receiving no intervention. The distribution of free booster seats combined with education on their use, had a marked beneficial effect, as did incentives (for example, booster seat discount coupons or gift certificates) combined with education. Education-only interventions also produced beneficial outcomes. One of the studies evaluated the effectiveness of the enforcement of a booster seat law, but did not detect an effect on usage.
The authors concluded that the current evidence suggests that several types of interventions aimed at increasing the use of booster seats among children aged four to eight years, are effective. However, there is still a need for further high quality trials, especially those conducted outside of the USA and Australia, where current research dominates.