Combining cellphone use with driving
May 29 2014
Chandigarh and Delhi administrations have imposed a ban on the use of cellphones while driving. The picture in the US is similar where the New York City prohibits the use of both types of cellular phones by cab and car service drivers. Although several cities and countries have taken measures to cut down cellphone usage while driving, still many countries have adopted a “wait and see” approach and not decided to impose such bans for now. Considering a divided view on the issue, one could ask, is driving while using cellphones really safe today? What are the current risks involved?
The Société de l’assurance automobile du Québec (SAAQ) conducted a study in 2003. Questionnaires were sent to 1,75,000 drivers and analysis was done on the 36,078 who responded. Driving habits, risk exposure, collisions over the past 24 months, socio-demographic information, and cellphone use was asked. Questionnaires were supported with data from cellphone companies and accident records held by police. The study found that the overall relative risk (RR) of having an accident for cellphone users when compared with non-cell phone users averaged 1.38 across all groups. When adjusted for kilometres driven per year and other crash risk exposures, RR was 1.11 for men and 1.21 for women. They also found that increased cellphone use correlated with an increase in RR.
The consistency of increased crash risk between hands-free and handheld cellphone use is at odds with legislation in many locations that prohibits hand held cellphone use but allows hands-free use. Research shows, however, that driving while using a hands-free cellular device is not safer than using a hand held cellphone. The increased cognitive workload involved in holding a conversation, not the use of hands, causes the increased risk. For example, a Carnegie Mellon University study found that merely listening to somebody speak on a phone caused a 37 per cent drop in activity in the parietal lobe, where spatial tasks are managed.
Although the above results suggest that cellphone use while driving is dangerous, there are also facts to suggest otherwise. For example, a recent research in this area at Harvard University has revealed that cellphone use while driving poses a risk to the driver, to other motorists, and to pedestrians; however, these risks appear to be small compared with other daily risks.
Based on present research, the estimated voluntary risk of fatality for user of a cellphone driving a vehicle is about six fatalities per million drivers. Also, the present involuntary risk of a pedestrian or other motorist being killed by a cellphone user driver is about one fatality per million drivers. These numbers are way less than those of the risks associated with drunken driving at 31 fatalities per million drivers, driving without safety belts of about 50 fatalities per million drivers and pedestrian struck and killed in motor vehicle crash of about 22 fatalities per million people in the US. Although many of these latter numbers look scary than those of the cellphone use, one reason for the low fatalities with cellphone usage could be the fact that most calls are made in traffic jams when people cannot reach their destinations in time.
Driving distractions caused by cellphone use is getting research attention; however, the scientific literature on the dangers of driving while sending a text message from a mobile phone, or texting while driving, is limited. A simulation study at the Monash University accident research centre has provided strong evidence that both retrieving and, in particular, sending text messages has a detrimental effect on a number of critical driving tasks. Specifically, negative effects were seen in detecting and responding correctly to road signs, detecting hazards, time spent with eyes off the road, and (only for sending text messages) lateral position. Market research by Pinger, a company selling a voice-based alternative to texting reported that 89 per cent of US adults think that text messaging while driving is “distracting, dangerous and should be outlawed.”
On July 27, 2009, the Virginia Tech Transportation Institute released preliminary findings of their study of driver distraction in commercial vehicles. Two studies, comprising about 200 long-haul trucks driving 3 million combined miles, used video cameras to observe the drivers and road; researchers observed a total of 4,452 safety-critical events, which includes crashes, near crashes, crash-relevant conflicts, and unintended lane deviations. About 81 per cent of the safety critical events had some type of driver distraction. Text messaging had the greatest relative risk, with drivers being 23 times more likely to experience a safety-critical event when texting. The study also found that drivers typically take their eyes off the forward roadway for an average of four out of six seconds when texting, and an average of 4.6 out of the six seconds surrounding safety-critical events.
So, what’s the bottom line? The need for the hour is that before any major policy decisions are made about cellular phones and texting, government and industry should work together to produce a richer body of knowledge on both the risks and benefits of using cellular phones while driving. They should also collect better scientific information on risks and benefits, and in the interim, should encourage more selective and prudent use of cellular phones while driving through vigorous public education programmes.
(The writer is on the faculty of Indian Institute of Technology, Mandi, India)