The Seville study on bike ridership and bike safety
Here are some of the results:
Here’s what they found: bike network connectedness seems to immediately pay off in the form of lower risk to people biking. The risk of a biking trip in Seville seems to have fallen dramatically in 2007 and stayed mostly flat afterward. No other single variable predicted bike safety as well as that single yes/no question: Has a network been built yet?
More accurate still was a formula that took into account both variables — the length of bikeways built and that yes/no question about whether or not the network had been connected.
In other words: Generally speaking, every additional mile of protected bike lane somewhere in the city improved safety. But network connections improved safety most.
Here is a summary, here is the study itself. For the pointer I thank Roland Stephen.