The effects of heat waves on traffic collisions require investigation to improve traffic safety during extreme heat events. A time-stratified case-crossover design was used to examine associations between heat waves and traffic collisions in Alabama between May and September from 2009 to 2018. We derived a heat wave index, defined as the daily mean temperature greater than the 95th percentile for two or more consecutive days, by meteorological data from Phase 2 of the North American Land Data Assimilation System. We obtained traffic collision records from the Alabama Department of Transportation. A nonsignificant and negative association between traffic collisions and heat waves was noted, with a 1.4 percent decrease (95 percent confidence interval [CI] [−3.1 percent, 0.4 percent]) in traffic collisions on heat wave days compared to non–heat wave days. Similar results were found when the analysis was stratified by driver-related factors (i.e., gender, age, race, employment status, and driver residence distances), vehicle-related factors (i.e., vehicle usage), and collision-related factors (i.e., rural or urban roads, speed limits, and intersections). A significant and positive association was observed on heat wave days without precipitation, however (23.5 percent increase; 95 percent CI [7.3 percent, 42.3 percent]). In conclusion, traffic collisions were not associated with heat waves in many collision-related conditions in Alabama.

热浪对交通碰撞的影响需要调查以提高极端高温事件期间的交通安全。时间分层的案例交叉设计用于检查 2009 年 5 月至 2018 年 5 月至 9 月期间阿拉巴马州热浪与交通碰撞之间的关联。我们得出了一个热浪指数，定义为两个地区的日平均温度高于 95%或更多连续天数，由北美土地资料同化系统第 2 阶段的气象资料得出。我们从阿拉巴马州交通部获得交通碰撞记录。注意到交通碰撞和热浪之间不显着和负相关，下降了 1.4%（95% 置信区间 [CI] [-3.1%, 0. 4%]）与非热浪日相比，热浪日的交通碰撞事故。当分析按驾驶员相关因素（即性别、年龄、种族、就业状况和驾驶员居住距离）、车辆相关因素（即车辆使用）和碰撞相关因素（即、农村或城市道路、限速和十字路口）。然而，在没有降水的热浪日观察到显着的正相关（增加 23.5%；95% CI [7.3%，42.3%]）。总之，在阿拉巴马州的许多与碰撞相关的情况下，交通碰撞与热浪无关。车辆相关因素（即车辆使用）和碰撞相关因素（即农村或城市道路、限速和交叉路口）。然而，在没有降水的热浪日观察到显着的正相关（增加 23.5%；95% CI [7.3%，42.3%]）。总之，在阿拉巴马州的许多与碰撞相关的情况下，交通碰撞与热浪无关。车辆相关因素（即车辆使用）和碰撞相关因素（即农村或城市道路、限速和交叉路口）。然而，在没有降水的热浪日观察到显着的正相关（增加 23.5%；95% CI [7.3%，42.3%]）。总之，在阿拉巴马州的许多与碰撞相关的情况下，交通碰撞与热浪无关。