This paper describes a procedure for developing accident modification factors (AMFs) by using a cross-sectional study. It is recognized that AMFs are most accurately derived from controlled experiments and observational before-after studies. However, the execution of experiments and before-after studies is not always practical or feasible. The procedure described in this paper is intended to be used in this situation. The procedure is demonstrated through the development of a curve radius AMF for rural two-lane highways.
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