NCHRP Project 17-63: Guidance for the Development and Application of Crash Modification Factors

The overall objective of this project is to provide guidance for the development and application of crash modification factors. To achieve this objective, this research has three development activities. The first activity is to develop guidelines for the calibration of current CMFs to assess treatment effectiveness at sites for which the site characteristics may be different from those represented by the sites whose data were used to develop the CMF. These characteristics include: geographical location, terrain, traffic demand, geometric design, traffic control features.

The second activity is to develop guidelines describing how existing and future CMFs can be combined to evaluate their overall safety effect for a single location at which multiple treatments are applied. The third activity is to develop procedures for formulating and calibrating future CMFs that identify key influential site characteristics. The guidelines are being developed for practitioner s and the procedures are being developed for researcher applications