Motor vehicle occupant injury and related hospital expenditures in children aged 3 years to 8 years covered versus uncovered by booster seat legislation.

BACKGROUND: Although most states have infant restraint laws, booster seat legislation for older children has not been implemented universally despite evidence of effectiveness. We examined injury and expenditures for motor vehicle traffic (MV) occupant injury among 3 year to 8 year olds covered versus uncovered by booster seat legislation.
METHODS: Age, state of residence/hospitalization, and month of injury were used to examine injury, deaths, and expenditures due to MV occupant injury in children covered versus uncovered by booster seat legislation. Data sources included Kids Inpatient Database 2003 and Web-based Injury Statistics Query and Reporting System. Statistical analyses used chi, Fisher's exact, and analysis of variance. Odds ratios were calculated with 95% confidence intervals (CI).
RESULTS: Children covered by booster seat legislation were less likely to be hospitalized for MV occupant injury than uncovered children (odds ratio, 0.78; 95% CI, 0.69-0.88). MV occupant injury constituted a smaller proportion of total injury expenditures in children covered (4.9%) versus uncovered (6.9%) by booster seat legislation. Covered children residing in areas with zip code incomes above the median had 26% lower MV occupant/total injury (p = 0.001) compared with 13% lower MV occupant/total injury for those below the median income (p = 0.0712). The proportion of injury dollars spent for MV occupant injury was higher in self-pay children for covered (7.8%) and uncovered (8.9%) children.
CONCLUSIONS: This study suggests that booster seat laws are associated with a lower proportion of injury expenditures for MV occupant injuries in booster seat-aged children. Observed income disparities raise questions regarding whether access to booster seats, quality of affordable seats, and proper use and/or enforcement strategies impede legislative effectiveness.