Transportation Research Institute, Hasselt University, Wetenschapspark 5, BE-3590 Diepenbeek, Belgium.
Accid Anal Prev. 2014 Jan;62:426-31. doi: 10.1016/j.aap.2013.05.003. Epub 2013 May 14.
Speed is one of the main risk factors in traffic safety, as it increases both the chances and the severity of a crash. In order to achieve improved traffic safety by influencing the speed of travel, road authorities may decide to lower the legally imposed speed limits. In 2001 the Flemish government decided to lower speed limits from 90km/h to 70km/h on a considerable number of highways. The present study examines the effectiveness of this measure using a comparison group before- and after study to account for general trend effects in road safety. Sixty-one road sections with a total length of 116km were included. The speed limits for those locations were restricted in 2001 and 2002. The comparison group consisted of 19 road sections with a total length of 53km and an unchanged speed limit of 90km/h throughout the research period. Taking trend into account, the analyses showed a 5% decrease [0.88; 1.03] in the crash rates after the speed limit restriction. A greater effect was identified in the case of crashes involving serious injuries and fatalities, which showed a decrease of 33% [0.57; 0.79]. Separate analyses between crashes at intersections and at road sections showed a higher effectiveness at road sections. It can be concluded from this study that speed limit restrictions do have a favorable effect on traffic safety, especially on severe crashes. Future research should examine the cause for the difference in the effect between road sections and intersections that was identified, taking vehicle speeds into account.
速度是交通安全的主要风险因素之一，因为它增加了事故发生的可能性和严重程度。为了通过影响行驶速度来提高交通安全，道路管理部门可能会决定降低法定限速。2001 年，弗拉芒政府决定将许多高速公路上的限速从 90 公里/小时降低到 70 公里/小时。本研究使用前后对比研究来考虑道路安全的一般趋势效应，来评估这一措施的有效性。共纳入了 61 个路段，总长度为 116 公里。这些地点的限速在 2001 年和 2002 年受到限制。对照组由 19 个路段组成，总长度为 53 公里，整个研究期间限速为 90 公里/小时。考虑到趋势，分析表明限速限制后碰撞率下降了 5%[0.88；1.03]。在涉及严重伤害和死亡的事故中，效果更大，下降了 33%[0.57；0.79]。在交叉口和路段的单独分析中，路段的效果更高。从这项研究可以得出结论，限速限制确实对交通安全有有利影响，特别是对严重事故。未来的研究应考虑到车辆速度的差异，进一步研究路段和交叉口之间效果差异的原因。
