Presentation | 2013

Safety Benefits of Median Installations in Utah

Brigham Young University


  • Introduction
  • Background
  • Selection of Analysis Sites
  • Analysis Procedure
  • Raised Median Results
  • Conclusions


  • Hierarchical Bayesian Poisson regression is an effective method for evaluating before and after studies of traffic safety projects
  • The methods are robust to the use of only small amounts of data
  • Any type of crash may be modeled and multiple covariates may be included in extremely flexible ways
  • This study provides an analysis of safety at locations where raised medians have been installed
  • Results indicate a significant improvement in terms of both crash frequency and frequency of severe crashes along corridors where raised medians were installed
  • Results from all sites show frequency of crashes reduced by 39% and frequency of severe crashes reduced by 44% after the installation of raised medians
  • Raised medians are one tool to aid in meeting the goal of ZERO Fatalities in the state of Utah
Effects, Medians
Median, Utah, safety