Toward the application of Wrong Way Driving countermeasures in European countries: Identification of the effectiveness and potential benefits of new technologies using a systematic review

Objective: Wrong Way Driving (WWD) is a very dangerous phenomenon for all road users. Although it occurs less frequently than other types of road collisions, every year in Europe results in crashes with severe consequences in terms of injuries and fatalities. Through a systematic review of the literature, this study aimed to identify the most effective countermeasures to avoid or mitigate injuries caused by WWD to foster their introduction in European countries. Methods: The study used the methodology of Systematic Review of the international scientific literature. Initially, the scientific literature was analyzed to investigate the research topic in-depth and identify the keywords to be used for retrieving all relevant studies. The systematic search was then performed on the most relevant digital databases, identifying 505 documents, which were reduced to 328 after removing duplicates. These were screened and analyzed in three stages: title, abstract, and full text. The final set of documents were thoroughly examined and sorted according to the following criteria: solution category, type of study, and countermeasure analyzed. In addition, a comparison of the effectiveness of promising solutions was carried out. Results: Seventeen papers were ultimately included and categorized into three types of countermeasures: Simple Signals, Intelligent Technological Solutions (ITS), and Road Design. Simple Signals can help reduce wrong-way driving events but are not always sufficient to prevent them. Practical solutions exist for different situations, yet wrong-way driving maneuvers may still occur despite their implementation. Considering ITS, Rectangular Rapid Flashing Beacons (RRFBs) are the most effective solution, followed by Light Emitting Diode (LED) systems. These solutions, combined with conventional signs, can reduce wrong-way driving events and collisions up to 60-85% with expected benefit-cost ratios up to 23. Regarding Road Design, improved layouts at intersections and entrances/exits of high-traffic roads, along with the use of barriers and appropriate devices, can help reduce WWD events. Conclusions: Intelligent Technological Solutions, particularly RRFBs, have been extensively and successfully tested on United States roads, with proven positive effects for crash reduction. Given their relative ease of implementation, such solutions are the most promising for addressing and mitigating the phenomenon of wrong-way driving in the European road context. Based on the findings of this study, a proposal for a tailored countermeasure suitable for implementation within the European countries was proposed.