Risk factors for severe injuries among front seat occupants in side impact crashes

With the adoption of effective passive safety measures to protect occupants in frontal crashes, interest on advancing side impact crashworthiness is raising. Our goal was to assess the main risk factors for severe injuries among adult front-seat passengers in side crashes. USA NASS CDS data (1998-2005) on side crashes were analyzed. Belted drivers and front-seat occupants 18 years old or older in vehicles no older than 16 years old were identified. Personal, crash and vehicle characteristics such seating position, age, gender, vehicle age, model year, wheelbase length, weight, longitudinal and lateral delta V, the presence of a front-seat passenger in the case of drivers, intrusion, side impacted (near side or far side), and type of object impacted (vehicle or fix post) were evaluated for their impact on modifying the likelihood of dying or sustaining AIS2+ or 3+ overall and by body region using multivariate Poisson ordinal regression models with the weighted data. Analyses were stratified by seating position. 5581 subjects met inclusion criteria, representing 2314218 victims. The results showed consistent and significant injurious effects related to vehicle intrusion and occupant ageing. Injurious effects for drivers were also identified in relation to the lateral delta V whereas lateral airbag inflation improved outcomes. Several other variables showed specific effects in regards to body-region specific injuries. Type of vehicle impacted, near- vs. far- sided crashes, vehicle age, weight and length or the occupant gender or height had little impact, as did to have a co-pilot in the case of drivers.