Abstract

This study proposes advanced safety assessment methods in the perspectives of prediction performance and practicality. This study thus develops three different safety assessment approaches (simulated conflicts-incorporated, estimated conflicts-incorporated, and intersection operational attributes-based safety performance function) and utilizes two existing approaches (annual average daily traffic-based and simulated conflicts-based safety performance functions. These five safety assessment approaches are compared in terms of crash prediction performance at intersections and practicality representing the required efforts in implementing a method. The results showed that the simulated conflicts-incorporated safety performance function approach was best in terms of prediction performance while the annual average daily traffic-based safety performance function approach was best in the practicality aspect. The discussion on trade-off between prediction performance and practicality then followed based on the analysis on the prediction performance and practicality aspects. This study will be a reference to safety assessment practitioners when they need to assess safety on roadways and to select an appropriate safety assessment method with limited resources.