Considering the number of people who have been involved in crashes associated with driver distractions, it is important to understand the characteristics of distracted driving on public roadways. While experiments have indicated that driver distractions are associated with slower driving speeds, the methodologies tend to have limited external validity. Observational studies are often conducted under limited circumstances – be it time or location. Therefore, in order to better understand the nature of driver distractions, the authors investigated the relationships between driving speed, posted speed limits, and phone handling frequency through naturalistic driving data obtained (via disruptive technology) from 8,240 mobile application users on state-maintained highways throughout Texas. As a measure of manual distractions, a phone handling rate (PHR; times/hours driven) was calculated based on phone rotations. Within-subject comparisons were drawn for driving speed and posted speed limits under normal driving conditions and distracted conditions. The analysis revealed a strong negative correlation between PHR and driving speed (r_s = -0.87). Paired t-tests revealed significantly lower driving speeds (p = 0.000 < 0.01, d = -0.48, η = 0.69) and posted speed limits (p = 0.000 < 0.01, d = -0.20, η = 0.42) during phone handling events when compared to driving without phone handling. On average, users drove 3.26 mph slower in distracted conditions than in undistracted conditions. Driving speed had a larger effect size than posted speed limits. The findings were in line with existing theories and experiments as well as other observational studies conducted at fixed locations. Although this research did not reveal causal relations, it is noteworthy that speed reduction with manual distractions was observed under real road conditions. Spatial analyses are recommended to conduct in order to paint a more thorough picture of speed reduction, its relationship to space, and crash risks related to distracted driving.

考虑到涉及驾驶员分心的事故的人数，重要的是要了解在公共道路上分心驾驶的特征。尽管实验表明驾驶员分心与较慢的驾驶速度有关，但这些方法往往具有有限的外部有效性。观察性研究通常是在有限的情况下进行的-无论是时间还是地点。因此，为了更好地理解驾驶员分心的性质，作者通过从状态保持高速公路上的8,240个移动应用程序用户获得的自然驾驶数据（通过破坏性技术）调查了行驶速度，张贴的速度限制和电话处理频率之间的关系。在整个德克萨斯州。作为分心的手段，根据电话旋转次数计算电话处理速率（PHR；驱动的时间/小时）。在正常驾驶条件和分心条件下，对驾驶速度进行了内部比较，并发布了速度限制。分析显示，PHR与行驶速度之间存在很强的负相关性（r _s = -0.87）。配对的t检验显示出较低的行驶速度（p = 0.000 <0.01，d = -0.48，η= 0.69）和公布的速度限制（p = 0.000 <0.01，d= -0.20，η= 0.42），与没有电话处理的驾驶相比。平均而言，分心情况下的使用者行驶速度比不分心情况下的速度慢3.26英里/小时。行驶速度的影响大小大于公布的速度限制。这些发现与现有的理论和实验以及在固定位置进行的其他观测研究相一致。尽管这项研究没有揭示因果关系，但值得注意的是，在真实的道路条件下，可以通过手动分心来降低速度。建议进行空间分析，以更全面地了解减速，速度与空间的关系以及与分心驾驶有关的撞车风险。