Answer
Speed cameras and average speed checks are both very effective in reducing crashes, but the latter are more effective. A meta-analysis of speed enforcement studies [36], shows that camera enforcement results in a 19% reduction of the total number of crashes and a 21% reduction of the number of serious and fatal crashes. A meta-analysis of average speed check studies [37] shows these checks result in a 30% reduction of the total number of crashes and a 56% reduction of the number of serious and fatal crashes. For more information see SWOV fact sheet Traffic enforcement.
