One third of the car accident deaths of children (under 13) are easily preventable. Yes, it's as easy as actually using a car seat or seat belt. Car seats are a lot like racing seats, and are definitely the safest place for a kid. Despite this, one in four parents drive with unsecured children in their cars.
Remember that the vast majority of car seats are improperly installed too, and that parents should take thier car seats to a local fire department to be checked after installation.