Here’s a couple of new nominations for the 2012 Cycling Science award. If you would like to suggest others, please use the reply form at the bottom of this page.
Out for the count
City planners need the right information to make the best decisions for encouraging cycling. Unfortunately the best information isn’t always available so they compromise and try to extract it from other sources.
For example, they should use accurate traffic counts when assesing the need for road design changes and the construction of better facilities for cycling, either cycle lanes or separated cycle paths.
The trouble is, they sometimes rely on those induction loops embedded in the asphalt and that are often there as part of the traffic signal system. They believe they detect every wheel that crosses them. They are so, so wrong.
While it’s common for the loops to ignore cyclists altogether, it seems from research at Ohio State University that they can’t always detect the lumps of metal that are cars and trucks.
Some of the induction loop counters were wrong by a massive 52%. Such inaccurate data must never be used in designing cycling facilities on or adjacent to the highway.
There are three things that careful researchers avoid:
1. Entering the febrile arena of discussion about bicycle helmets
2. Questioning head on accepted wisdom, such as that which evolves from Cochrane reviews
3. Taking the time to correct the mistakes made by others.
So three cheers to Rune Elvik at the Institute of Transport Economics in Norway and editor of Accident Analysis and Prevention.
He’s done all three in a dense little paper, which will infurate the pro-helmet lobby because one of its conclusions is that “no overall effect of bicycle helmets could be found when injuries to head, face or neck are considered as a whole.