The National Highway Traffic Safety Administration (NHTSA) has revised its child restraint guidelines to be categorized by age rather than by type of child seat in order to keep pace with the latest scientific and medical research and the development of new child restraint technologies. Under the
new guidelines, issued March 21, 2011, NHTSA is advising parents and caregivers to keep children in each restraint type, including rear-facing, forward-facing and booster seats based on the aging out principle or by reaching the maximum height/weight requirements, for as long as possible before moving them up to the next type of seat.