Statistical analyses based on NASS CDS data from 1998-2008 and 17 combined years of State data from Kansas, Washington, and Nebraska estimate the effects of early graduation from child restraint seats to booster seats and of early graduation from booster seats to lap and shoulder belts. The principal findings are that among 3- and 4-year-olds there is evidence of reduced risk of injury when restrained with the recommended child restraints rather than in booster seats. This reduction depends on injury severity, and may be as large as 27 percent for non-disabling to fatal injuries. This effect may be more pronounced in the 3-year-olds, although sample sizes are too small to draw statistical conclusions. Among 4- to 8-year-olds there is strong evidence of reduced risk of injury when restrained by booster seats rather than lap and shoulder belts. The magnitude of this effect for the combined database is a 14 percent reduction in risk of any type of injury, but the effect varies depending on data source and injury severity. Estimates varied from no effect to a 45 percent reduction of MAIS equal/smaller 2 injuries based on CDS data. (Author/publisher)
Samenvatting