Preventing injuries to children through compulsory automobile safety seat use.

Effects of Michigan's law requiring all young children to be restrained when traveling in automobiles were assessed. Data on all reported residents of the state who were involved in crashes from 1978 through 1983 were examined using times-series analysis methods. Reported restraint use among injured children younger than 4 years of age involved in crashes increased from 12% before to 51% after the law was implemented. More importantly, a 25% decrease in the number of children younger than 4 years injured in crashes was associated with the law. A reduction of this magnitude was repeatedly found, whether analyzing the raw frequency of children injured, the rate of injured children per crashed vehicle, the rate of injured children per vehicle mile traveled, or the proportion of all injured occupants accounted for by young children. The substantial increase in restraint use and decrease in number of children injured appear to be direct results of the law, because similar changes did not occur among any of the comparison age groups. The 25% reduction in the number of young children injured means that an estimated 522 children per year are protected from injury because of Michigan's compulsory child restraint law.