Meta-analysis of the effect of road safety campaigns on accidents

► Meta-analysis of 67 studies evaluating the effect of road safety campaigns on accident numbers. ► Weighted average effect of campaigns is a 9% reduction in accidents. ► Meta-regression analyses indicate that accident reduction is greater where there is personal communication and roadside delivery of the campaign message. ► Enforcement is also beneficial in terms of accident reduction according to the meta-regression analyses. ► Campaign efficacy may be greater in the short term if the message is delivered in a way that is proximal in time and space to the target driver behaviour.