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Driving impaired

Roadway Tragedies: When Will the Madness End?

16 Jun, 17 | by Angy El-Khatib

[Angy El-Khatib] This post is from guest blogger Bethesda Yohannes. Bethesda is an intern at the Injury Prevention Center of Greater Dayton in Dayton, Ohio, United States. She is currently a second year undergradute student in the College of Education and Human Ecology at Ohio State University. 

As the journey to reduce traffic-related fatalities continues, more information is becoming available to aid in this expedition. Traffic fatalities have been present ever since the time of buggies and horse-drawn carriages. Although traffic-related casualties have occurred since the beginning of vehicle transportation, the tolerance for these accidents remains low due to the high potential for prevention. Recently, the Insurance Institute for Highway Safety (IIHS) published a report which explores the correlation between mortalities and factors such as weekends, unemployment, and technology.

The 2017 IIHS report reveals that traffic-related death rates increase during weekends and holidays. According to the IIHS, increasing death rates can be linked to risky behaviors that take place during these periods. Although roadway deaths have decreased since 1998, the pattern of deaths remains stagnant. As Charles Farmer, IIHS Vice President for Research and Statistical Services, said, “The riskiest times remain risky.” However, with proper enforcements these rates can decline. New Years Eve and [American] Independence Day are the two holidays with the highest, traffic-related fatality rates; however, when increased impaired-driving enforcement (i.e. – DUI checks) are initiated during these holidays, traffic-related fatalities went down 5% during New Years Eve and 13% during Independence Day.

Although traffic-related death patterns have remained the same, they have decreased within the last decade; this can partly be attributed to advances in technology relating to motor vehicles. Improved safety technology and newer car models have resulted in slightly reduced driver death rates. Factors, such as the size of the vehicle, are being investigated; for example, small, four-door cars were found to have the highest death rate (87 deaths per million) whereas SUVs had the lowest death rates (6 deaths per million). Crash avoidance technology and “self-driving” vehicles could, in theory, reduce crash rates. However, as Farmer points out, “Improvement in vehicle technology are important, but we also need to address old problems such as speeding and driving while impaired.”

Unfortunately, improvements in the economy do not always equate to lower death rates; the decline of unemployment rates due to a flourishing economy have been linked to the increase in traffic fatalities. This increase is not only due to an improved economy, but rather the increase of vehicle miles as more people attend work. If the U.S Bureau of Labor Statistics prediction of an annual decline of 1.7% in unemployment from 2014 to 2024 continues, it is expected that the , traffic-related death rates will reduce from 35,092 in 2015 to 34,400 by 2024. An improved economy may be related to increases in highway fatalities or accidents at the workplace, but lifestyle factors could also play a role. We know that smoking, alcohol use, obesity, and physical inactivity rise when unemployment rates fall.

The exact correlation between unemployment and traffic-related death rates are still being researched as more data about the multiple factors continues to be collected. Researchers remain puzzled about the most effective and efficient methods to prevent traffic-related deaths, but efforts continue. Partnerships with court systems, law enforcement agencies, hospitals, and other community organizations (such as Mothers Against Drunk Driving or the American Automobile Association) allow injury prevention professionals to identify high-risk individuals and make a population-level impact. Surveillance of traffic-related crashes and reports, such as the IIHS report, are necessary to better inform policy and/or community-level interventions.


Media and injury prevention

6 Jul, 15 | by Bridie Scott-Parker

As an injury prevention researcher, I am often dismayed at the way in which injuries, risk, and injury prevention efforts are portrayed in the media. I clearly recall being disgusted as an idealistic teenager, having read a newspaper article regarding the untimely death of a peer who had been killed during a police chase. The police involved were vilified, and the article waxed lyrical about how the teen was a pillar of the community, which was a very different representation of reality. Since this time I have taken most media with a grain of salt, preferring to investigate myself, and to make up my own mind, rather than blithely accepting everything that is said, written and printed. I realise this is not the case for everyone, however, and the media has an amazing capacity to influence public opinion, which is highly relevant for injury prevention efforts in particular.

My post today was prompted by the publication of a paper in Accident Analysis and Prevention by Brubacher, Desapriya, Chan, Ranatunga, Harjee, Erdelyi, Asbridge, Purssel, and Pike. Brubacher and colleagues noted that British Colombia introduced new road safety laws focused on impaired driving, speeding and distracted driving in 2010, and examined the focus of the injury-related media during the period May 2010 to December 2012. From an injury prevention perspective, clearly these laws are designed to keep British Colombians safe – not just drivers, but others with whom they share the road such as pedestrians. Pleasingly 51% of reports which mentioned the new laws were supportive, but disappointingly 11% of reports were against the changes: in real terms this means that every tenth article during this time was NOT supportive of these injury prevention efforts.

To maximise our capacity as injury prevention researchers, policy-makers and practitioners, I believe it is vital to work with media as much as possible, clearly and consistently emphasising benefits rather than giving extensive airtime to perceived downsides such as being ‘unfair’ (downsides of which personally I struggle greatly to relate – I think being injured or killed by a distracted, impaired, and/or drunk driver is unfair).

Texting laws reduce traffic fatalities

7 Aug, 14 | by gtung

Quick post here to highlight a nice study authored by Alva O. Ferdinand and colleagues at the University of Alabama at Birmingham that examined the impact of state texting laws on motor vehicle fatalities in the United States. I came away with two important findings from the study. First, primary enforcement (which means that officers can stop someone for only texting) texting bans were associated with a 3% decrease in traffic fatalities. Second, primary texting laws targeting teens were associated with an 11% decrease in traffic fatalities in that group. Given the tremendous variation that exists among the US states, including many states that have no texting restriction, this study provides important evidence to advance these laws. Links to the study and related media coverage below.

More on Driving under the influence of Marijuana

19 Feb, 14 | by gtung

There was a fascinating article published on the issue of driving under the influence of marijuana this past Monday in the New York Times.

Marijuana and driving is an issue of increasing relevance as US states continue to legalize medical marijuana and Colorado and Washington State have now legalized recreational marijuana.  The challenges associated with setting a specific standard for driving under the influence of marijuana have already been discussed on this blog but in a nutshell there is one major challenge. That challenge is that similar blood levels of THC can mean very different things for various people and represent very different levels of driving impairment.  Chronic users can have relatively high levels of THC regularly in their blood that correspond to much lower deficits in driving performance compared to novice users.  It also doesn’t help that marijuana blood levels currently have to be tested for with a blood or urine samples compared to a Breathalyzer test for alcohol.

The interesting position emphasized in the article and put forth by Eduardo Romano at PIRE and Mark Klein at UCLA is that alcohol is so much more dangerous than marijuana when it comes to driving under the influence that efforts to change DUI policy should focus on alcohol as opposed to marijuana and on lowering the current alcohol BAC levels from 0.08 to 0.05.  A recent paper published by Romano in the Journal of Studies on Alcohol and Drugs did not find a statistically significant increased risk of a fatal crash associated with marijuana when controlling for demographics and alcohol.  Other research suggests that any measurable THC is associated with a doubling of crash risk.  Compare this to alcohol though where the crash risk increases nine fold at the 0.08 level for adults (it is even higher for those under 21).

The data does seem to indicate that driving while under and influence of alcohol is more dangerous compared to driving under the influence of marijuana but the policy environment seems receptive to taking action on marijuana and driving while the recent recommendation by the National Transportation Safety Board to move alcohol BAC levels from their current level of 0.08 to 0.05 doesn’t seem to have much traction (at least yet).

Given the current receptivity to address marijuana related issues I think it make sense to take advantage of it by doing the relevant research and then making informed policy decisions.  This does not take away from the importance of moving alcohol BAC levels in the US from 0.08 to 0.05 but the current window of opportunity seems to be marijuana specific and it is not clear to me that advancing marijuana related DUI policies detracts from efforts to advance alcohol DUI policies.

Would you drive blindfolded?

6 Jan, 14 | by Bridie Scott-Parker

I hope you said ‘no’ in response to that question! If you didn’t, maybe you shouldn’t be sharing the road with the rest of us sane people!

To me, driving whilst distracted is just like driving blindfolded. In either scenario, you cannot and do not see the road in front, to the side, or behind you. You cannot detect or react appropriately to driving hazards that you would otherwise be able to avoid. Yet a simple drive/walk/cycle down any busy street is likely to mean that you will encounter someone who is distracted, that is, someone who is effectively driving whilst blindfolded.

Here in Australia, distracted and inattentive driving is recognised as one of our Fatal Five (e.g., see Sources of distraction include external mechanisms both inside the vehicle such as mobile phones and in-car navigation devices or outside the vehicle such as roadside advertising, but may also include oft-unrecognised internal mechanisms such as extreme emotions. Whilst distracted driving is not unique to the young driver, by virtue of their driving inexperience they are at increased risk of harm as a result of distracted driving. Naturalistic driving research recently published in The New England Journal of Medicine (see revealed that the risk of a crash/near-crash among young drivers increased significantly if drivers were

* dialling or reaching for a cell phone,

* sending or receiving text messages,

* reaching for an object other than a cell phone,

* looking at a roadside object, or

* eating.

Crash risk increased significantly for experienced drivers who were dialling a cell phone (risks associated with accessing internet and texting were not measured). The Authors noted that “The secondary tasks associated with the risk of a crash or near-crash all required the driver to look away from the road ahead.” Effectively driving blindfolded. This suggests that efforts should address the ‘blindfolded driving’ not only of young drivers through interventions such as graduated driver licensing programs as recommended by the Authors, but blindfolded driving by all drivers of all ages and driving experiences.



Notes from Canada on bullying and DWI

13 Sep, 13 | by Barry Pless

Two items that I trust will be of some interest to readers of this blog.

The first is from Paul Kells, the former CEO of Safe Communities in Canada. Now that SC has been absorbed by Parachute (the new umbrella organization – no pun intended) he has launched a new career and one part of that is to foster Up-Standers — people who make a difference. In a recent email he described Travis Price and David Sheppard, both from Nova Scotia, who took on the challenge of preventing bullying. In Pauls words, this is what happened:  “Back in 2007, Travis Price and David Shepherd, then in Grade 12, rallied hundreds of students at Central Kings Rural High School in Nova Scotia to wear pink t-shirts to school to stand up to bullies who had harassed a younger boy the day before for wearing pink.  The story was picked up by media and since then millions of people in different parts of the world wear pink to show their support for those who are bullied. Click here to read the original CBC news story.The provincial government at the time legislated the second Thursday of every September to be “Pink Shirt Day” and children throughout the province participate. Other provinces started their own anti-bullying days as well.The story of these two boys is a testament to the fact that standing up (vs. taking the position of a bystander) can make a big difference. Today, the Up-Standers group is working with the Canadian Red Cross to create a national anti-bullying day. The intent is to change the mindset around bullying. Previous large scale culture change campaigns have worked before – seat belts, drinking and driving and recycling are a few examples.When you put on your pink shirt, remember how much impact this seemingly small gesture can make.   Paul Kells   Workplace Respect and Safety Champion, Culture Change Expert and Inspiring Speaker

The second is a new report from the Traffic Injury Research Foundation (TIRF) that reveals a worrying trend: the growth of DWI offenses among women. The report was based on a qualitative study that included a review of the literature about female drunk drivers. As well as the increases in arrests among women for DWI it pointed “to gaps in knowledge pertaining to their profile and characteristics, experiences in the criminal justice and treatment systems, and the types of strategies and interventions that are most effective with this population. Consequently, TIRF conducted a follow-up exploratory case study in 2012 that involved cases drawn from California, Michigan, Missouri and New York. “The design of this hypothesis-generating study included interview focus groups with more than 150 female offenders representing diverse backgrounds and experiences in the system. It also involved interviews with 36 experienced practitioners representing different phases of the criminal justice and treatment systems.  The objectives of the study were to:
– Create a foundation that could inform the development of much needed research initiatives as well as prevention efforts and effective interventions tailored towards female drunk drivers.
– Explore the life histories of convicted female drunk drivers and the ways that their history may contribute to their offending.
– Examine women’s experiences in the criminal justice and treatment systems.
– Explore the experiences of criminal justice and treatment professionals in supervising this offender population.
Click here to download the executive summary. –
Click here to download the full report. –

Editors comment: I am not a great fan of qualitative research and even less happy about focus groups but there are clearly some important findings here that should trouble us because we have long assumed (at least I have) that DWI mostly involved men. To discover that women are a large and growing part of the  problem is noteworthy.


Hands-free doesn’t mean distraction-free

12 Jun, 13 | by gtung

The AAA Foundation for Traffic Safety in the United States has just published a report titled, “Measuring Cognitive Distraction in the Automobile.”

The report, based on research led by David Strayer from the University of Utah, concludes that many activities that don’t require the use of hands still pose a significant cognitive distraction that results in increased crash risk. Of the six different types of potentially distracting activities examined, including talking on a cell phone either hand-held or hands-free, the most distracting activity was using a speech–to–text system. This type of system allows users to dictate emails, texts, Facebook posts, etc. and is already available in some high-end infotainment systems.

The findings of this report probably don’t come as good news to many major automobile manufacturers who are increasingly placing complex infotainment systems into new cars and seem to be banking on hands-free interaction with these systems being safer. The vice president for public affairs at the Alliance for Automobile Manufacturers was quoted in a recent New York Times article as saying, “we are concerned about any study that suggests that handheld phones are comparably risky to hands-free systems we are putting in our vehicles.”

The National Highway Traffic Safety Administration, the federal agency in the United States responsible for automobile safety, issued voluntary guidelines in April of this year to try and get automobile manufacturers to limit the distractions from infotainment systems.  But there is a clear trend in the industry moving in the exact opposite direction and there doesn’t seem to be a lot of optimism about the auto industry changing course without mandatory legislation or regulation.

Marijuana and driving: How much is too much?

10 Jun, 13 | by gtung

Two U.S. states, Colorado and Washington, have recently legalized the recreational use of Marijuana and both are struggling with the question of how much is too much when it comes to Marijuana and driving.  Colorado and Washington have both recently passed legal limits for tetrahydrocannabinol or THC in the blood at 5 ng/ml but Washington’s is a “per se” law while Colorado’s is not.  A per se law sets an intoxication standard based purely on the concentration in the blood.  So in Colorado, even if a driver is above the 5 ng/ml limit they have the opportunity to present evidence that they are not impaired.

Some marijuana advocates argue that the 5 ng/ml standard is too low and that some medical marijuana users are always above that level.  What is the right level?

Below is a very unscientific examination of the issue by a local television station in Washington State.

There doesn’t appear to be a scientific consensus on what the maximum THC blood level should be.  The National Highway Traffic Safety Administration in the U.S. is researching the issue with results expected next year.  Until more research becomes available the debate continues.

National Transportation Safety Board Recommends a move from 0.08 to 0.05 BAC laws in the U.S.

15 May, 13 | by gtung

On May 14, 2013 the National Transportation Safety Board (NTSB) in the United States released a report titled, “Reaching Zero: Actions to Eliminate Alcohol-Impaired Driving.”

 The National Transportation Safety Board is a legislatively mandated independent federal agency that is charged with, among other things, making recommendations related to transportation safety.  The NTSB report is substantial and it notes that alcohol-impaired driving remains a major safety issue in the United States with close to one-third of all highway fatalities associated with alcohol.  The report makes a number of recommendations to U.S. states that include the following taken directly from the report.

  • Reduce the per se blood alcohol concentration (BAC) limit for all drivers,
  • Conduct high-visibility enforcement of impaired driving laws and incorporating passive alcohol sensing technology into enforcement efforts,
  • Expand the use of in-vehicle devices to prevent operation by an impaired driver,
  • Use driving while intoxicated (DWI) courts and other programs to reduce recidivism by repeat DWI offenders, and
  • Establish measurable goals for reducing impaired driving and tracking progress toward those goals.

The recommendation that seems to have already garnered the most attention is the recommendation to lower state blood alcohol concentration limits to 0.05g/dl.

The current standard that exists in all U.S. states is 0.08g/dl while most developed countries have a 0.05g/dl standard.  Not surprisingly, there appears to be strong resistance to the 0.05g/dl BAC recommendation from the beverage industry.  A representative from the American Beverage Institute was quoted in the following article as saying, “Moving from 0.08 to 0.05 would criminalize perfectly responsible behavior” and “further restriction of moderate consumption of alcohol by responsible adults prior to driving does nothing to stop hard-core drunk drivers from getting behind the wheel.”

And a representative from the Beer Institute was quoted as saying, “…we strongly encourage policymakers to direct their efforts where we know we can get results: by focusing on repeat offenders and increasing penalties on those with BAC of (0.15) or more.”

Scientific research on the topic summarized in the NTSB report however, clearly supports the assertion that moving to a 0.05g/dl BAC standard would save additional lives.

It will be interesting to see how responsive the states are to the NTSB’s recommendations.  In an effort to help motivate the states, the NTSB also recommends that some type of incentive grants be offered to states if they adopt the best practice recommendations including the 0.05 g/dl BAC standard.





Distractions – a growing injury issue moving beyond the car?

25 Apr, 13 | by gtung

Distracted driving has justifiably received a tremendous amount of attention in the injury prevention field. But the issue of distractions and the associated injury risk might be getting even bigger and becoming more relevant outside of the motor vehicle realm.

There is lots of interesting speculation about an impending boom in wearable computing. Several major technology players seem set to release various types of wearable computing devices. The big ones are Apple Watch and Google Glass.

Check out a video of Google Glass here:

The video has undeniable cool factor (at least to me) but it also shows people engaged in activities (flying a plane, high wire acrobatics, etc.) where I would think unnecessary distractions pose a significant injury risk.

While neither Apple Watch nor Google Glass has been commercially released, there are already wearable computing devices available now.  Oakley currently makes ski goggles that display various types of information including speed and there are several other companies that make eyewear intended for athletes such as runners and cyclists.

A recent New York Times article did a nice job of summarizing some of the concerns, including risk of injury, associated with these devices.

The appeal of these types of devices is clear to me. As an avid cyclist, I would love to know real-time data on speed, cadence, heart rate, and power output but the potential dangers associated with these devices are not yet well understood. It will be interesting to see if the predicted boom in wearable computing actually happens and if it does (and it probably will) it could create a significant challenge for the field of injury prevention.

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