Redelmeier D A, Tibshirani R J
Department of Medicine, University of Toronto, ON, Canada.
N Engl J Med. 1997 Feb 13;336(7):453-8. doi: 10.1056/NEJM199702133360701.
Because of a belief that the use of cellular telephones while driving may cause collisions, several countries have restricted their use in motor vehicles, and others are considering such regulations. We used an epidemiologic method, the case-crossover design, to study whether using a cellular telephone while driving increases the risk of a motor vehicle collision.
We studied 699 drivers who had cellular telephones and who were involved in motor vehicle collisions resulting in substantial property damage but no personal injury. Each person's cellular-telephone calls on the day of the collision and during the previous week were analyzed through the use of detailed billing records.
A total of 26,798 cellular-telephone calls were made during the 14-month study period. The risk of a collision when using a cellular telephone was four times higher than the risk when a cellular telephone was not being used (relative risk, 4.3; 95 percent confidence interval, 3.0 to 6.5). The relative risk was similar for drivers who differed in personal characteristics such as age and driving experience; calls close to the time of the collision were particularly hazardous (relative risk, 4.8 for calls placed within 5 minutes of the accident, as compared with 1.3 for calls placed more than 15 minutes before the accident; P<0.001); and units that allowed the hands to be free (relative risk, 5.9) offered no safety advantage over hand-held units (relative risk, 3.9; P not significant). Thirty-nine percent of the drivers called emergency services after the collision, suggesting that having a cellular telephone may have had advantages in the aftermath of an event.
The use of cellular telephones in motor vehicles is associated with a quadrupling of the risk of a collision during the brief time interval involving a call. Decisions about regulation of such telephones, however, need to take into account the benefits of the technology and the role of individual responsibility.
由于人们认为驾车时使用移动电话可能会引发碰撞事故，一些国家已对在机动车内使用移动电话加以限制，其他国家也在考虑制定此类法规。我们采用了一种流行病学方法——病例交叉设计，来研究驾车时使用移动电话是否会增加机动车碰撞风险。
我们研究了699名拥有移动电话且遭遇机动车碰撞事故的司机，这些事故造成了重大财产损失但未导致人员伤亡。通过详细的计费记录，分析了每个人在碰撞当天及前一周的移动电话通话情况。
在为期14个月的研究期间，共拨打了26798次移动电话。使用移动电话时发生碰撞的风险比不使用移动电话时高出四倍（相对风险为4.3；95%置信区间为3.0至6.5）。对于年龄和驾驶经验等个人特征不同的司机，相对风险相似；接近碰撞时间的通话尤其危险（事故发生前5分钟内拨打的电话相对风险为4.8，而事故发生前15分钟以上拨打的电话相对风险为1.3；P<0.001）；免提装置（相对风险为5.9）与手持装置相比（相对风险为3.9；P无显著性差异）并无安全优势。39%的司机在碰撞后拨打了紧急服务电话，这表明拥有移动电话在事故发生后可能具有优势。
在涉及通话的短时间内，在机动车内使用移动电话会使碰撞风险增加四倍。然而，关于此类电话的监管决策需要考虑该技术的益处以及个人责任的作用。
