Factors associated with clinically significant head injury in children involved in motor vehicle crashes.

OBJECTIVE Head injury is the most common cause of death for child occupants in motor vehicle crashes (MVCs). The morbidity associated with nonlethal MVC-related head injuries is of great clinical consequence as well. The purpose of this study was to identify the frequency of, and risk factors for, clinically significant head injury (CSHI) in child occupants in MVCs. METHODS A large, child-specific crash surveillance system linking insurance claims data to telephone survey data was utilized. Qualifying crashes involved model year 1990 or newer vehicles in crashes with one or more child occupants (age 4 to 15 years) occurring in 15 U.S. states. Data were accrued between March 2000 and December 2007. A probability sample of crashes was selected for telephone survey with the driver of the insured vehicle. A clinically significant head injury, as reported by the child's parent using a validated survey, included concussions, skull fractures, and intracranial hemorrhages. Multivariate logistic regression was used to identify factors associated with a CSHI. RESULTS During the period of study, completed interviews were obtained on 19,075 children aged 4-15, representing 318,527 children involved in 219,511 crashes. The overall rate of CSHI in child occupants was 1.08 percent. Factors associated with an increased risk of head injury included rollover (odds ratio [OR] = 8.60, 95% confidence interval [CI] 6.40-11.57) and near-side impact crashes (OR = 2.39, 95% CI 1.73-3.30) vs. frontal impact; lack of restraint (OR = 3.13, 95% CI 2.26-4.33) vs. restrained; and driver age < 25 years (OR = 1.43, 95% CI 1.12-1.81) vs. driver age ≥ 25 years. Some factors varied based on occupant age, and younger child age had a protective effect on the risk for head injury. CONCLUSION The risk of CSHI for 4- to 15-year-old child occupants was 1.08 percent. Several demographic and crash factors were associated with CSHI in child occupants. This information may help inform design safety initiatives.