Expected Differences and Unexpected Commonalities in Mortality, Injury Severity, and Injury Patterns Between Near Versus Far Occupants of Side Impact Crashes

Abstract

To compare injury patterns and outcomes of near- and far-side collisions. Near- and far-side occupants in the Crash Injury Research and Engineering Network (CIREN) were compared for mortality and the occurrence of severe injuries (maximum abbreviated injury scale [MAIS] 3+). Regression models, adjusting for confounders, examined death and MAIS 3+ injuries as outcomes and near- or far-side position as an independent variable. CIREN findings were compared with those of the Crash Outcome Data Evaluation System (CODES), and the Maryland Automated Accident Reporting System. Of the 380 cases, 72% were in the near and 28% in the far position. Mortality was similar between groups within CIREN. Near-side occupants experienced a higher frequency of MAIS 3+ injuries for the thorax, abdomen, and lower extremities, and fewer MAIS 3+ head injuries than far-side occupants (35% vs. 46%, p = 0.06). Regression models revealed similar risk of MAIS 3+ head injuries among near- and far-side occupants. The most common structures contacting the head in far-side crashes (N = 62) were opposite side structures (52%) and other occupants (13%). Similar risks of head injuries among near- and far-side occupants were observed for the CODES data; however, lower risks of death were present among far-side drivers involved in crashes, based on CODES and Maryland Automated Accident Reporting System. Despite a lower incidence of thoracic, abdominal, and lower extremity injuries, far-side occupants experienced a similar risk of head injuries to that of near-side occupants. Contact patterns suggest that restraint systems fail to keep far-side occupants' heads from striking opposite side structures or other occupants.