In addition, pediatricians should counsel parents to follow the AAP recommendations for the utmost car seat safety rather than simply follow state laws, which may allow "graduation" to the next level before the child is large enough, Dr. Hoffman said.
"The laws of physics will always trump the laws of the state," he concluded.
All authors filed conflict of interest statements with the AAP, and any conflicts have been resolved through a process approved by the AAP Board of Directors, according to a statement in the journal.
A list of formal car seat inspection stations is available at http://www.seatcheck.org. If your community does not have an inspection station, you can find a child passenger safety technician in your area on the National Child Passenger Safety Certification Web site (http://cert.safekids.org).