Study: Cellphone bans associated with fewer urban accidents

November 15, 2012

Cellphones and driving go together like knives and juggling. But when cellphone use is banned, are drivers any safer?

It depends on where you're driving, a study by University of Illinois researchers says.

The study found that, long-term, enacting a cellphone ban was associated with a relative decrease in the accident rate in urban areas. However, in very , cellphone bans were associated with higher accident rates than would otherwise be expected.

"The main idea is to use the eye test when it comes to cellphone use," says study leader Sheldon H. Jacobson, a professor of computer science and mathematics at the U. of I. "If you look around and it's busy, it's a good idea to put the cellphone down and not use it when driving."

The Illinois study, published in the journal Part A: Policy and Practice, is set apart by two factors: the length of time and the method of measuring driver density.

The study examines long-term trends of accident rates and their association with cellphone bans, comparing seven years of driver data in New York – the first state to institute a statewide ban – and neighboring Pennsylvania, which has no ban. Both states have similar weather patterns and wide diversity in size and population density of counties.

"Most other studies focus on a very short-term analysis," Jacobson said. "A law is enacted; what's the impact immediately? We try to take a much longer view and look at the impact not just over six months to a year, but over several years."

While most studies define driver density by licensed drivers per square mile, the Illinois researchers looked at the number of per mile of to get a better estimate of traffic volume by county. They classified counties as urban, rural or very rural, and performed to look for trends in accident rates in each class over time.

Across all three classes, enacting a cellphone ban was associated with an initial rise in accident rate, followed by a steeper decline than would otherwise be expected, although the magnitude differed in each class of counties. In higher driver density areas, there was a clear, statistically significant, association between the enacting of a cellphone ban and relative reduction in personal injury accidents after seven years. By contrast, such bans in very rural areas were associated with a relative increase in accident rates over the same period.

"What we found in our research is that the cellphone ban was associated with different outcomes in different groups of counties," said industrial and enterprise systems engineering researcher Douglas King, a co-author of the study. "Based on this research, it suggests that a blanket cellphone ban may not always lead to a greater benefit. Based on the seven-year time period that we were able to examine, the outcome in each group of counties after the ban was not uniformly beneficial."

The cause of the slight increase of accidents in very rural areas is unknown, although Jacobson and King hypothesize that lower enforcement or other factors unique to rural driving may contribute.

"The other possible explanation is that in lower driver density areas, the number of accidents is smaller, and as a result the data collected isn't as rich," Jacobson said "This could be just a statistical anomaly."

Whatever the reason for the relative increase in rural accidents, the relative decline in urban accidents in New York versus Pennsylvania was clear: After the initial ban enactment, accident rates declined and continued to be lower over time.

"This is the kind of research that definitely should encourage densely populated areas to enact these laws," King said. "There's sufficient evidence to support it. When you start getting into rural and very rural areas, I think you have to have to take it in a case-by-case basis. But for urban areas, the evidence is substantial."

Explore further: Study: Cell-phone bans while driving have more impact in dense, urban areas

Related Stories

Would cellphone ban dial back 'distracted driving'?

December 21, 2011

The National Transportation Safety Board (NTSB) — an independent federal agency responsible for investigating transportation accidents and promoting transportation safety — called for a complete end to cellphone ...

Driving while phoning danger as bad as drink-driving

June 12, 2008

Motorists who use cellphones while driving make as many, if not more, driving errors as clinically drunk drivers, according to educational psychologist Professor Michael Townsend. He says the proposed ban on hand-held cellphone ...

Research shows hands-free phones just as risky

December 15, 2011

(AP) -- Like it or not, when someone is talking to you, your brain is listening, processing and thinking about what's being said - even when you're in the driver's seat trying to concentrate on traffic.

Recommended for you

How to cut your lawn for grasshoppers

November 22, 2017

Picture a grasshopper landing randomly on a lawn of fixed area. If it then jumps a certain distance in a random direction, what shape should the lawn be to maximise the chance that the grasshopper stays on the lawn after ...

Plague likely a Stone Age arrival to central Europe

November 22, 2017

A team of researchers led by scientists at the Max Planck Institute for the Science of Human History has sequenced the first six European genomes of the plague-causing bacterium Yersinia pestis dating from the Late Neolithic ...

Ancient barley took high road to China

November 21, 2017

First domesticated 10,000 years ago in the Fertile Crescent of the Middle East, wheat and barley took vastly different routes to China, with barley switching from a winter to both a winter and summer crop during a thousand-year ...


Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Nov 15, 2012
Different people need different laws for their well-being. I think the way we go about government needs to take this simple fact into consideration a *lot* better. It could be that some people need to operate in a republic, and others are better off in an internet-based omniarchy or democracy-by-postal-system. We're all different. What I *do* know is that my wellbeing is maximized in a government free of other people's imaginary friends, and I support any secession or federal amputation that brings me closer to living in such a place. In addition, many laws interact with different functions inherent to a population, that should *automatically* switch modes when different conditions are met. Our government shouldn't be static anymore. It should be a body of code that can make adjustments to laws on-the-fly.
5 / 5 (1) Nov 15, 2012
Impossible. Limiting freedom can never be good for the people.

Or so I am told by my Libertarian/Randite friends.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.