ANN ARBOR, Mich. -- Booster seat-aged children are twice as likely to suffer serious injury or death in a car crash than younger children but a new study shows they may be less likely to have car seats inspected for proper use.
Less than a quarter of car seat and booster checks analyzed in the new University of Michigan Health System study were conducted in children ages four and older at car seat inspection stations in Michigan. Just 1 in 10, or 11 percent of inspections, covered booster seat-age children ages 4-7 while half were for rear-facing car seats.
The findings, which appear in this month's issue of the Journal of Trauma, also show that roughly a third of booster seat-age children who did have seats checked left an inspection in a safer restraint than when they arrived.
"Booster seats seem less technical and complicated than installing an infant seat, which may lead parents and families to worry less about using them incorrectly," says senior author Michelle L. Macy, M.D., M.S. of the University of Michigan's C.S. Mott Children's Hospital and the Child Health Evaluation and Research Unit (CHEAR).
"We know that older kids are at particular risk of injury from a car crash. Our study suggests it may be beneficial for certified child passenger safety technicians to focus more on providing education and guidance on prolonged use of booster seats."
Unintentional injury remains the leading cause of death and disability for children over the age of one in the U.S. Children ages 4-12 are more likely to suffer significant abdominal injuries as a result of switching from booster seats to seatbelts too soon. These injuries, known as 'seat belt syndrome', include intra-abdominal, spinal cord, and facial injuries.
Booster seats have been shown to reduce the risk of serious injury by 45 percent in children aged 4-8 when compared with seat belt use alone but there are reportedly lower rates of proper restraint use among older kids. Authors point to such factors as lack of knowledge about the safety benefits of booster seats and risk to child passengers.
Child passenger safety initiatives also generally focus most on car seat inspections for infants and toddlers, authors say. The study analyzed data from 4,531 car seat inspections (1,316 that occurred through Safe Kids Huron Valley and 3,215 through Safe Kids Greater Grand Rapids). Children older than four were more likely to have a sibling who underwent a car seat inspection - many may have even been brought along with no intention from the parent of having the older child's seat evaluated.
"Study after study shows that caregivers often need support and direction when choosing and installing child restraints and that they are often using them incorrectly, which puts child passengers at unnecessary risk of harm," says lead author Amber Kroeker, M.P.H., who was with CHEAR at the time of the study.
"This gap can be addressed in car seat inspections, which are free and offered in most communities, but our findings indicate low use of this service by parents of older children."
In a recent survey of 1000 parents by Safe Kids Worldwide, seven out of ten parents did not know that optimal vehicle belt fit may not be obtained until a child reaches a height of 57 inches, and nine out of ten parents prematurely transition their child from a booster seat to a vehicle seat belt.
"Injury risk in motor vehicle accidents has been dramatically reduced for infants and toddlers because of an increased focus on proper restraints," Kroeker says. "We want to see the same outcomes for older children."
Kroeker is now an injury prevention program coordinator at Randall Children's Hospital - Legacy Emanuel in Portland, Ore. Amy Teddy, B.S., also contributed to this report.
Funding: This research was funded in part by a pilot grant from the University of Michigan Injury Center through the Centers for Disease Control and Prevention (R49CE002099)
Reference: "Car Seat Inspection Among Children Older than Three: Using Data to drive practice in child passenger safety," Journal of Trauma, September, 2015.