FABB Blog

The project has been carried out as a randomized controlled trial with 6,800 volunteer cyclists. After random selection, half of the group – the test group – got the bicycle jacket at once and promised to wear it each time they biked during a year. The other half of the group composed a control group that got the bicycle jacket after the closing of the project, i.e. after a year.

The safety effect of the bicycle jacket was analysed by comparing the number of self-reported accident for the test and control group. The self-reported accidents showed that the test group had 38% fewer personal injury accidents with other road users – so-called multi-party accidents – than the group who did not wear the bicycle jacket. If one only looks at accidents between participants and vehicles, the difference is 48%. The differences are statistically significant at 5% level. In the test group, 37% of the involved parties in an accident reported that they were not wearing the bicycle jacket or any other bright-coloured garment when the accident occurred.

The Danish Road Traffic Accident Investigation Board (AIB) has a working hypothesis stating that lack of visibility can be among the reasons for the higher accident risk for cyclists (AIB, 2008). This hypothesis is supported by a project on the use of permanent running lights for cyclists completed in collaboration with the Traffic Research Group at Aalborg University and Odense Municipality. The project documents that the use of permanent running lights significantly reduces the accident risk for cyclists. Specifically, the probability of cyclists being involved in multi-party accidents is reduced with 47 %. These accidents are typically the most severe ones for cyclists, and the reduction most likely caused by the cyclists’ increased visibility. (Madsen et al., 2013)