Context Although more than a dozen states have ratified laws that require booster
seats for children older than 4 years, most states continue to have child
restraint laws that only cover children through age 4 years. Lack of booster
seat effectiveness data may be a barrier to passage of stronger child restraint
Objectives To quantify the association of belt-positioning booster seats compared
with seat belts alone and risk of injury among 4- to 7-year-old children and
to assess patterns of injury among children in booster seats vs seat belts.
Design, Setting, and Population Cross-sectional study of children aged 4 to 7 years in crashes of insured
vehicles in 15 states, with data collected via insurance claims records and
a telephone survey. A probability sample of 3616 crashes involving 4243 children,
weighted to represent 56 593 children in 48 257 crashes was collected
between December 1, 1998, and May 31, 2002.
Main Outcome Measure Parent report of clinically significant injuries.
Results Injuries occurred among 1.81% of all 4- to 7-year-olds, including 1.95%
of those in seat belts and 0.77% of those in belt-positioning booster seats.
The odds of injury, adjusting for child, driver, crash, and vehicle characteristics,
were 59% lower for children aged 4 to 7 years in belt-positioning boosters
than in seat belts (odds ratio, 0.41; 95% confidence interval, 0.20-0.86).
Children in belt-positioning booster seats had no injuries to the abdomen,
neck/spine/back, or lower extremities, while children in seat belts alone
had injuries to all body regions.
Conclusion Belt-positioning booster seats were associated with added safety benefits
compared with seat belts to children through age 7 years, including reduction
of injuries classically associated with improper seat belt fit in children.