This Latin, and before that Greek, adage (perhaps more recognisable in the form of its English equivalent ‘More haste less speed’) has stood the test of time. Speed is a known determinant of road crash death. The maximum vehicle travel speed that we permit on our roads is a design setting that, in combination with other road design features, establishes the crash injury performance of that road system. Reducing speeds at which road vehicles travel reduces both the frequency of crash and the forces transferred at the point of collision. Reducing frequency of crashes and magnitude of transferred force will decrease the number of serious crash injuries and severity of the injury sustained, and thus improve the crash injury performance of the road system. All else being equal, the speed permitted on the road needs can be set to deliver the crash injury performance outcome that is desired. The correlation between vehicle speed and crash injury has been universally accepted for as long as there have been speed limits on roads. What part of this problem do we still not understand? Two manuscripts published this year in Injury Prevention have focused on an answer to this question; it’s the intervention part. Each manuscript describes results from a natural experiment, with their respective research locations being on either side of the Atlantic. Both …
Language: en
LA - en SN - 1353-8047 UR - http://dx.doi.org/10.1136/injuryprev-2020-043711 ID - ref1 ER -