Vehicles increasingly have airbags designed to protect the head and/or torso in side impacts. The objective of this study was to estimate the efficacy of side airbags in preventing driver deaths in passenger cars struck on the near side (next to driver). Relative to cars without side airbags, rate ratios (RR) and 95 percent confidence intervals (95% CI) for deaths per near-side collision for model years 1997-2002 during 1999-2001 were computed for side airbags designed to reduce both head and torso injuries and those designed to reduce mainly torso injuries. To attempt to address confounding from extraneous protective factors associated with side airbags, near-side RRs were adjusted for driver mortality in frontal and rear impacts, which are unaffected by side airbags. Driver fatality risk in near-side crashes was reduced by 45 percent in passenger cars equipped with head/torso-protection side airbags (adjusted RR=0.55; 95% CI=0.43-0.70) and by 11 percent in cars with airbags that protect only the torso (adjusted RR=0.89; 95% CI=0.79-1.01; nonsignificant). Major reductions in risk were observed when passenger cars with head-protection airbags were struck on the left by cars/minivans (adjusted RR=0.26; 95% CI=0.20-0.36) or pickup trucks/sport utility vehicles (adjusted RR=0.47; 95% CI=0.26-0.88). Head-protection side airbags were associated with significant struck-side risk reductions in two-vehicle collisions, among male and female drivers, and among drivers ages 16-64. Protective effects associated with torso-only airbags were marked in single-vehicle crashes (adjusted RR=0.62; 95% CI=0.41-0.95). Torso-only airbags also were associated with significant reductions in fatality risk among drivers ages 16-64 and male drivers. Conclusions: Side airbags that include head protection, typically combined with torso protection, have significantly reduced near-side driver deaths. Torso-only side airbags generally have been less effective in protecting drivers. The mortality experience of occupants in vehicles with side airbags should continue to be followed. (Author/publisher)
Samenvatting