Car phones and car crashes: some popular misconceptions.

in a widely cited medical journal, in which we reported an association between cellular telephone calls and motor vehicle collisions. During that week we participated in more than 50 media interviews because we think scientists have an obligation to communicate with society. During subsequent years we have stayed in the academic field analyzing the limitations, implications and misquotations of our research. We are not activists on a public crusade. We are not lobbyists with a mission. Careful science tends to follow a conservative design, is written in a modest manner and emphasizes the limitations of current data. As a consequence, all of our past research provided plenty of fodder for those who oppose laws that prohibit using a cellular telephone while driving. The purpose of this commentary is to take the alternative position and to explain how our research might have underestimated the risks associated with using a cellular telephone while driving. Other studies in support of potential regulations are not reviewed here. In our research, we found that drivers were 4 times more likely to have a collision when using a cellular telephone than when not using a cellular telephone. What we wish we had explained more clearly in our article, however, was that this increase was not calculated in comparison to the risk of collision under ideal circumstances of no distractions. Actually, the increase was relative to the risk of collision when the driver drove with his or her usual background distractions. Making calls on a cellular telephone is distinctly more risky than listening to the radio, talking to passengers and other activities commonly occurring in vehicles. Traditional statistics create subdued impressions. In our work, the 95% confidence intervals were skewed so the estimated relative risk spanned from 3 to 6. The records of telephone use were not accurate to the second and our measures of driving patterns were also inexact; together, such imprecision biased the risk estimate toward finding nothing. Our cohort also included a few drivers who did not call while driving, and this made the entire group seem a bit protected from collisions. In contrast, arguments based on anecdotes and not statistics can yield a dramatic impression (e.g., a news report that a driver was talking on a cellular telephone and smashed into another vehicle, killing 2 people). Our study evaluated drivers who owned a cellular teleCar phones and car crashes: some popular misconceptions