There must be a head or back light for bikes particilarly at night. It would be better if cyclist would wear reflectors so drivers around would easily see them. It must always be considered when biking at night in order to avoid such incidents.
Reflectors and reflective clothing cannot be counted on, not saying not to use them because they can work under idea circumstances. What are those idea circumstances you scream? The headlights of the car must hit the reflective item directly, if they don't they won't work, this is why road workers have gone to a safety vest that now has an LED array in the vest along with the reflective bands.
Read this:
http://www.visualexpert.com/Resources/pedestrian.html
https://www.bicycling.com/bikes-gea...of-being-seen-a-guide-to-safer-riding/slide/7
There was a study that indicated that with older people they could not see the reflective material as well as younger drivers, but they did notice reflective material that wasn't moving, but they did notice the up and down motion of reflective material like reflective ankle bands.
In what I think is a controversal study is this one out of the UK:
http://www.telegraph.co.uk/news/2017/11/26/cyclists-high-visibility-jackets-increase-odds-crash/ I'm not sure what to make of that, but I will say this, a rider needs to be using all available means to make themselves visible, that includes passive lighting (reflective stuff), but most importantly active lighting which is the key element.
I once saw a guy that had 9 rear tail lights, 4 head lights and everything reflected, if you missed him and hit him you needed your drivers license suspended for life!! He looked like a moving Christmas tree. Do I think a person needs to get that radical, probably not but it did show me something, the more lights you have the better you're seen. When I ride at night I use a cheap home improvement neon green safety vest with wide reflective bands (the neon doesn't do anything at night but it does show up during the dim daytime hours), I use a high reflective ankle bands, and some other reflective stuff that really is just banding that probably doesn't work all that well like the helmet, shoes, jacket, and my seat bag, I have a front flasher, a headlight on the bars, and a headlight on the helmet, I then have a tail light on the helmet, and one a bright one on the seat post. I had a another 3rd tail light and put it on the seat stay but it broke so I haven't replaced it yet, butI think I'm fine the way I am.
The other issue I read about lights is that according to a UK study that flashing lights confuse motorists as to how far they are away from a rider so they outlawed flashing rear and front lights. However a study done in Canada showed that flashing lights attracted the attention of motorists...so what do I thought...I use both flashing and constant, on the rear my helmet light flashes while by seat post light is on constant because that one is a 70 lumen light and the brightest one I have currently. When I get another brighter rear light I will make the brighter one the constant one and the other will be a flasher.
With people now mind numbed by texting while driving you should be using front and rear flashers during the day. Flashing light will attract their attention faster then a steady light during the day.