There are nearly a thousand bike related fatalities per year. Most fatal accidents involve a vehicle. Thus, separating bikes in physically separated bike path will likely reduce fatal accidents.

Source: Yes, protected bicycle lanes make streets safer for cyclists |

However, an estimated 90% of bike crashes do not involve a vehicle at all – but are instead bikes versus other bikes, bikes versus road way hazards, bikes versus pedestrian, bikes versus animals and so on.

Data on overall bike injuries is poor – but there are estimates of 1/2 million bike related injuries treated in ERs, and estimates of 1-2 million or so bike related injuries treated at urgent care, doctor’s offices, or self treated. Unfortunately, with poor quality injury data, and the media’s focus on fatalities, we might not be solving as much as we think.