Vehicle rollovers are one of the more severe crash modes in the US - accounting for 32% of all passenger vehicle occupant fatalities annually. One design enhancement to help prevent rollovers is Electronic Stability Control (ESC) which can reduce loss of control and thus has great promise to enhance vehicle safety. The objectives of this research were (1) to estimate the effectiveness of ESC in reducing the number of rollover crashes and (2) to identify cases in which ESC did not prevent the rollover to potentially advance additional ESC development.
All passenger vehicles and light trucks and vans that experienced a rollover from 2006 to 2015 in the National Automotive Sampling System Crashworthiness Database System (NASS/CDS) were analyzed. Each rollover was assigned a crash scenario based on the crash type, pre-crash maneuver, and pre-crash events. The Insurance Institute for Highway Safety ESC availability database was matched to each NASS/CDS case vehicle by the vehicle make, model, and model year. ESC effectiveness was computed using the quasi-induced exposure method.
From 2006-2015, control loss was a factor in 29.7% of the 1,339,407 vehicle rollovers. ESC was standard equipment in 177,644 of vehicles involved in these events. Our study estimated that ESC was effective in reducing the overall number of rollover crashes by 13.3%. ESC was more effective at reducing rollover crashes due to control loss with a reduction of 50.6%. ESC is particularly effective for high center of gravity vehicles such as light trucks, SUVs, and vans. Travelling too fast for the road conditions was the most common reason rollovers due to control loss were not prevented despite the presence of ESC.