Compelling evidence was presented last month at an American Academy of Pediatrics (AAP) conference that booster seats can save lives for kids in cars until they've reached close to adult stature (4 feet 9 inches tall).

As reported on MedPageToday, states that implemented booster seat laws recorded a decline in serious injuries from motor vehicle crashes for children 4 to 8 years old. States that lacked such regulations saw no changes in the same study period.

Although the study has not been published in a peer-reviewed journal, and therefore is considered preliminary, it’s hardly the first to confirm the wisdom of strapping children into booster seats. But it also supports the idea of using the seats for older children.

The AAP recommends that children be secured in a belt-positioning booster seat until they reach 4 feet, 9 inches in height. Usually, that’s between the ages of 8 and 12.

There is no federal effort to standardize booster-seat laws.

In the 10-year study, “Booster Seat Laws Reduce Motor Vehicle Fatalities and Injury,” there were 9,848 fatalities and incapacitating injuries in children ages 4 to 8. The rate of death and incapacitating injuries declined 20 percent for children 4 to 6 in states with booster seat laws, and 33 percent for kids 7 to 8. Children 4 to 6 with no or improper restraint were twice as likely to suffer death or an incapacitating injury, and members of the older group were four times as likely compared with properly boostered kids.

Children 4 to 6 who were restrained only by a lap/shoulder belt were 20 percent likelier to suffer death or an incapacitating injury, and 70 percent likelier if they were 7 or 8.

According to the Governors’ Highway Safety Association:

• All 50 states, the District of Columbia, Guam, the Northern Mariana Islands and the Virgin Islands require child safety seats for infants and children fitting specific criteria.
• Forty-eight states and the District of Columbia require booster seats or other appropriate devices for children who have outgrown their child safety seats but are still too small to use an adult seat belt safely.
• The only states lacking booster seat laws are Florida and South Dakota.
• Five states (California, Florida, Louisiana, New Jersey and New York) have seat belt requirements for school buses. Texas requires them on buses purchased after September 2010.

To find out more about the laws in your state, link here. For information about car seats and installation tips, visit the American Academy of Pediatrics site, and our post about rear-facing seats.