Exploring factors contributing to injury severity at freeway merging and diverging areas

Identifying factors that affect crash injury severity and understanding how these factors affect injury severity is critical in planning and implementing highway safety improvement programs. Factors which can be categorized in to classes such as driver-related, traffic, environmental and geometric design were considered to develop a statistical model that can be used to predict the effects of these factors on severity of injuries sustained from crashes. Police-reported crash data obtained from the Ohio Department of Public Safety (ODPS) at selected freeway merging and diverging areas in the State of Ohio was used for the development of the model. A generalized ordinal logit model or partial proportional odds model was applied to identify the factors that tend to increase the likelihood of one of five levels of injury severity: No Injuries, Possible/Invisible Injuries, Non-incapacitating Injuries, Incapacitating Injuries, or Fatal Injuries