In 2004 and 2005, a controlled trial involving 3845 riders was conducted in Odense, Denmark, to see if the lights installed on bicycles would have a positive impact on the safety of riders.
The non detachable permanent lights were installed on 1845 bicycles, and the control group was the cars of another 2000 riders without lamps, and the accident records were conducted for 12 months.
Finally, through comparative analysis of the data, the accident rate of riders with permanent lights decreased by 19%. The results show that the use of lighting during the day will have a positive impact on safety.
But at present, there are two kinds of arguments about the requirements of using lamps during the day: flashing or long-term lighting.
In the Netherlands, the use of strong light flashing is banned because they have found that too bright a flash can make people feel dazzled, which may affect the driver's judgment.
But in turn, flashing lights will also make it easier for drivers to notice you, even when using continuous light sources, it will also make it easier for the opposite car to notice you, giving you more space and more serious treatment on the road.
I guess it's possible for people to think of you as a motorcycle for a moment, which will make the vehicle think you're going to be faster and pay more attention to early response.