Poor Communication Weakens a New Study’s Public Safety Message about Drinking and Driving — Are There No Scientifically-Minded Editors Anywhere?

© 2011 Peter Free

 

21 June 2011

 

 

What were they thinking when they wrote this abstract/news release about drinking and driving?

 

David Phillips and Kimberly Brewer appear to have done a valuable study of the statistics regarding  1,495,667 fatal U.S. automobile accidents between 1994 and 2008 — but they botched properly communicating their findings in a way that would support their intended message.

 

Here is what the researchers’ Addiction abstract said:

 

Findings  Accident severity increases significantly even when the driver is merely ‘buzzed’, a finding that persists after standardization for various confounding factors.

 

Three mechanisms mediate between buzzed driving and high accident severity: compared to sober drivers, buzzed drivers are significantly more likely to speed, to be improperly seatbelted and to drive the striking vehicle.

 

In addition, there is a strong ‘dose–response’ relationship for all three factors in relation to accident severity (e.g. the greater the BAC, the greater the average speed of the driver and the greater the severity of the accident).

 

Conclusions  The severity of life-threatening motor vehicle accidents increases significantly at blood alcohol concentrations (BACs) far lower than the current US limit of 0.08%. Lowering the legal limit could save lives, prevent serious injuries and reduce financial and social costs associated with motor vehicle accidents.

 

© 2011 David P. Phillips and Kimberly M. Brewer, The relationship between serious injury and blood alcohol concentration (BAC) in fatal motor vehicle accidents: BAC = 0.01% is associated with significantly more dangerous accidents than BAC = 0.00%, Addiction, DOI: 10.1111/j.1360-0443.2011.03472.x  (early online publication, 20 June 2011) (paragraph split)

 

 

“What’s wrong with these statements and the message derived from them?”

 

A statistically significant relationship between data sets is not the same as a socially important or medically meaningful one.

 

The abstract provides no mathematical description of the analysts’ findings.  (It doesn’t even define “buzzed.”)  Consequently, it is not possible to estimate the importance of whatever magnitude exists.

 

If the article itself contains a better explanation, one will have to pay Addiction to find it.  Which few if anyone in the public sector are going to do, especially after reading such a lousy abstract.

 

It should be obvious that American policy-makers are not going to lower blood-alcohol standards without being persuaded that there is a dramatically meaningful rise in traffic-related injuries at relatively low blood-alcohol concentrations.

 

The Phillips-Brewer abstract conveys no math, instead relying on the more or less typical scientific persuasion style, “Do it because I said so.”

 

 

The University of California at San Diego did a similarly incompetent communication job

 

One would think that filtering a crappy science abstract through a savvy public relations/news department would clean up some of its communicative shortcomings, especially after accessing the study’s author(s).

 

Not in this case.

 

Here is what the University of California – San Diego said about the Phillips-Brewer study:

 

All the accidents included in FARS [Fatality Analysis Reporting System] are, by definition, severe. But the authors looked at different levels of accident severity by examining the ratio of severe injuries to minor ones.

 

 "Accidents are 36.6 percent more severe even when alcohol was barely detectable in a driver's blood," Phillips said. Even with a BAC of 0.01, Phillips and Brewer write, there are 4.33 serious injuries for every non-serious injury versus 3.17 for sober drivers.

 

© 2011 Inga Kiddera, Buzz Kills: No Amount of Alcohol Safe to Drive, UC San Diego Study Finds, University of California – San Diego (20 June 2011)

 

What does “36.6 percent more severe” mean?

 

Also — if one is using a registry of fatalities — how can one fatality be more severe than another?

 

Notice, too, that 4.33 is 36.6 percent greater than 3.17.  But that is a different observation than saying that “accidents are 36.6 percent more severe.”  (“More severe” means that I broke my arm, rather than stubbing my toe.)

 

The 4.33/3.17 ratio comparison does say that there are 36.6 percent more accidents in the severe category.  (Which presumably communicates what the study’s authors apparently intended to say, but did not.)

 

But even if the research authors and Ms. Kiddera had properly communicated that it was severity on a defined scale that they were talking about, they didn’t define the scale.

 

So again, readers are left to wonder whether the study’s findings are relevant to anything someone (who has not already been touched by driving-under-the-influence fatalities) cares about.

 

 

“Why does good communication of scientific findings matter?”

 

If I am a policy maker faced with a drinking public’s resistance to change, I am most probably not going to be especially motivated by the difference between 4.33 serious injuries versus 3.17 serious injuries.

 

Especially when the do-gooders behind the public safety message can’t communicate the importance of their work in understandable fashion.

 

 

The moral?

 

Thinking about messages, before talking and writing, is important.  Just making it into the media isn’t enough.

 

Stupid communications arguably do more harm than good.  Obtuse communication reduces one’s credibility as a source worth considering.