Road injuries are among the leading causes of loss of life and disability worldwide, and they are projected to make an increasingly important contribution to public health burdens over the coming decades. A study was published in The Bristish Journal of Medicine on the effect of 20 mph traffic speed zones on road injuries in London, 1986-2006.The objective was to quantify the effect of the introduction of 20 mph (32 km an hour) traffic speed zones on road collisions, injuries, and fatalities in London. The study is based on analysis of geographically coded police data on road casualties, 1986-2006. Analyses were made of longitudinal changes in counts of road injuries within each of 119,029 road segments with at least one casualty. Results: The introduction of 20 mph zones was associated with a 41.9% reduction in road casualties. The percentage reduction was greatest in younger children and greater for the category of killed or seriously injured casualties than for minor injuries. In areas adjacent to 20 mph zones casualties also fell slightly by an average of 8.0%. Conclusions 20 mph zones are effective measures for reducing road injuries and deaths. You can read
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