U.S. National Research Council * Transportation Research Board
This study focused on the link between crash severity and crash avoidance maneuvers. Various emergency lateral and speed control maneuvers were considered in response to different critical events that made the crash imminent. Partial proportional odds models that allowed for changes in effects across severity levels were estimated to accommodate the ordered-response nature of severity. The sample used for estimation consisted of data for single-vehicle crashes extracted from the General Estimates System crash database for the period from 2005 to 2009. Results showed the correlation between crash avoidance maneuvers and crash severity, with differences emerging for different critical events. Moreover, results showed two trends: (a) most drivers failed to act when facing critical events and (b) drivers rarely performed crash avoidance maneuvers that were correlated with a higher probability of lower crash severity. These trends suggest that efforts to understand the mechanisms of reactions to different critical events should be made to improve in-vehicle warning systems, promote responsible driving behavior, and design forgiving infrastructures.