While slides from a webinar are not always helpful without the recording to go with it, today's APBP webinar on "Is there safety in numbers for cyclists and pedestrians?" is an exception.
It all seems to be common sense conclusions but they provide the research to back up the important role that larger volumes of cyclists, road design and the presence of bike infrastructure play in reducing crash rates.
Two clarifications to note: first, crashes here refer only to motorists and peds or cyclists (not bike/bike or bike/ped) and second, there is an error in Luis M.'s conclusion slide (63 of 85). The blue line should read "Rates without refuge island" and the red line is "Rates with refuge island".