Surrogate measures of safety (SMoS) can enable quick, pro-active, and detailed safety evaluations by studying near-crashes. A critical concern regarding SMoS is their validity. This study focused on the validity of two commonly used SMoS indicators—minimum time to collision and post-encroachment time—with a specific focus on bicyclist–motor vehicle interactions. The study was divided into two main parts; the first part focused on observations at intersections in Scandinavia, and the second part focused on developing a crash model using data from 166 similar intersections. Nine signalised intersections in Scandinavia were observed for at least 24 h. During this time, each interaction between a bicyclist and a right- or left-turning motor vehicle was identified and trajectories for the road users were created. The corresponding SMoS values were then calculated. Three main results were found when comparing the results of the crash model with the SMoS analysis. First, there is a significant relationship between the expected number of crashes and both indicators. However, the results also suggest that this correlation might originate from the inherent connection between the indicators and the number of interactions between the studied road users. Finally, when the number of interactions is considered, the results show that the minimum time to collision with a threshold of 3–4 s produces the best results.

安全替代措施（SMoS）可通过研究近乎崩溃来进行快速，主动和详细的安全评估。关于SMoS的一个关键问题是其有效性。这项研究的重点是两个常用的SMoS指标的有效性-最小碰撞时间和侵占后时间-尤其关注骑车人与机动车之间的相互作用。该研究分为两个主要部分：第一部分着重于斯堪的纳维亚交叉路口的观测，第二部分着重于使用来自166个类似交叉路口的数据开发碰撞模型。在斯堪的那维亚的9个信号交叉口至少观察了24小时。在此期间，识别了骑自行车的人与向右转或向左转的机动车之间的每次互动，并为道路使用者创建了轨迹。然后计算相应的SMoS值。将碰撞模型的结果与SMoS分析进行比较时，发现了三个主要结果。首先，预期的撞车次数与两个指标之间都存在显着的关系。但是，结果还表明，这种相关性可能源于指标之间的固有联系以及所研究的道路使用者之间的互动次数。最后，当考虑相互作用的数量时，结果表明，最短碰撞时间为3到4 s阈值可获得最佳结果。结果还表明，这种相关性可能源于指标之间的固有联系以及所研究的道路使用者之间的互动次数。最后，当考虑相互作用的数量时，结果表明，最短碰撞时间为3到4 s阈值可获得最佳结果。结果还表明，这种相关性可能源于指标之间的固有联系以及所研究的道路使用者之间的互动次数。最后，当考虑相互作用的数量时，结果表明，最短碰撞时间为3到4 s阈值可获得最佳结果。