Background Cycling infrastructure aims to make cycling more convenient and safer for cyclists. We undertook a Cochrane review to assess the effectiveness of cycling infrastructure at reducing cycling injuries in cyclists.

Methods Sixteen databases, twelve websites and conference proceedings were searched up to March 2015. Eligible studies included RCTs, CBAs or an ITS evaluating a cycling infrastructure and reporting injuries or collisions. Two authors independently extracted study data and quality assessment.

Results Twenty one studies met inclusion criteria. Meta-analyses relating to cycle lanes on roads (rate ratio (RR) 1.21, 95% confidence interval (CI): 0.70 to 2.08) and cycle routes and networks (RR 0.68, 95% CI: 0.31 to 1.47) found no evidence that either were effective at reducing cycle collisions. From a narrative review, there was some evidence that 20 mph speed limits were effective at reducing collisions. Redesigning specific parts of cycle routes that may be particularly busy or complex in terms of traffic movement may reduce the risk of collision. The conversion of intersections with and without signals to roundabouts with cycle paths may reduce the odds of collision. Findings related to the instalment of Advanced Stop Lines, use of colour, cycle tracks and cycle paths suggest these neither reduce nor increase injury collisions in cyclists. There was some evidence that the conversion of intersections to roundabouts with cycle lanes marked as part of the circulating carriageway may increase cycle collisions. There was some evidence that continuing a cycle lane across the mouth of a side road with a give way line onto the main road may increase the risk of injury collisions in cyclists.

Conclusions Several designs of cycling infrastructure may reduce collisions. There is a paucity of high quality evaluations of cycling infrastructure. The use of adequate data collection periods and assessment of cycle flows would improve future evaluations.