SWOV is investigating the relationship between safety performance indicators and crash probability
Red light running at a 50 km/h intersections has been found to increase the risk of fatal crashes ten to fifteen times. This is evident from the SWOV research 'Risk factors investigated further: 50 km /h intersections', in which so-called safety performance indicators (SPI's) have been studied. SPI's can help policy makers to pursue a proactive road safety policy. This is also called a 'risk-based approach'.
In the research, SWOV not only elaborates the theory of SPI's somewhat further, but also examines whether a predetermined set of risk indicators could actually be found in fatal crashes. Those are speed, drink-driving , distraction, fatigue, no (correct) use of safety devices such as helmet or seatbelt and visibility in darkness. Not giving way and red light running have also been considered, with the latter-mentioned risk factor being studied in more detail.
Increased probability of crashes at 50 km/h intersections
A quantitative relationship was found between red light running at a 50 km/h intersection and fatal crashes, which results in an increased probability of a crashe of ten to fifteen times. To determine this, red light running was compared in a case-control study. For this purpose, the study compared the red light running at ’50 crossings’ with traffic light in all 20 fatal crashes that occured in one year in the Netherlands with non-crash involved behavior. .
SWOV project leader Letty Aarts: "The extent to which red light running leads to a larger risk of crashes, should be approached with some caution. After all, we have been able to base our findings on 20 crashes, over one year. In addition, we also need to keep an eye on the correctness and completeness of the available details about the crashes: in some cases it was not possible to determine with certainty that red light running had played a role in the crash. "
The methodology that has been followed to investigate SPI's for their usefulness offers perspective. At present, more research is being carried out, which further explores the method used to study other SPIs in the future. SWOV also looks at information from other data sources.
