Mixing Terminology on Drink-Driving Survey Causes Media to Pile On Midwest

April 25, 2008

Pity the upper Midwestern motorist – or, rather, the poor pedestrian that crosses his bleary-eyed path. According to a story on FOX News:

The upper Midwest has the worst drunken driving rates in the country, according to a government report that says 15 percent of adult drivers nationally report driving under the influence of alcohol in the previous year.

Wisconsin leads the way. The federal government estimates more than a quarter of the state’s adult drivers had driven under the influence. Rounding out the worst five are North Dakota, Minnesota, Nebraska and South Dakota.”

From Minnesota (MPR) to Florida (the Palm Beach Post), and along with the national news services like the Associated Press (“Study: Midwest has the worst drunken driving rates”), Lake Wobegon turned into Lake Woebegone. Naturally, this required a sociological explanation. As the AP reported:

Eric Goplerud, research professor at George Washington University Medical Center, said cultural and demographic issues probably have a role in the higher rates of driving under the influence in certain states. He said that religious affiliations in the Southeast often strongly discourage drinking, but that doesn’t occur so much in the upper Midwest. ‘A good part of the social life is around drinking,’”

The Milwaukee Sentinel Journal, on the other hand, just needed someone to explain why the findings required no explanation:

‘I’m not shocked, I’m not surprised,’ Nina J. Emerson, director of the Resource Center on Impaired Driving at the University of Wisconsin Law School, said of the latest report.

Nor did the finding startle Paul Moberg, senior scientist in the Population Health Institute at UW-Madison and co-author of a 2007 study on Wisconsin’s alcohol and drug use patterns.

‘Not really,’ he said. ‘I think that’s been what we’ve seen historically.’”

But did the government study really find what all the media accounts claimed it did?

The Substance Abuse and Mental Health Services Administration (SAMHSA), which is part of the Department of Health and Human Services, surveyed 127,283 drivers nationwide over the course of 2004, 2005, and 2006. And it describes the results as a measure of “driving under the influence of alcohol.”

Most people would assume (as many journalists did) that this refers to the proportion of drivers who were legally DUI, e.g., had blood alcohol levels (BAC) of .08 or more, the level at which they are legally intoxicated. But SAMHSA uses the phrase “driving under the influence” to mean having any measurable level of alcohol in the blood.

The problem with this approach is that it conflates legal with illegal drink driving – the person who has a drink after work and who has a BAC lower than 0.8 and the person who shouldn’t be in the driving seat.

Does it make sense to do this? If you assume that any amount of alcohol consumption should prohibit driving, then yes. This would mean that the presumptive level for intoxication should be set at .01 BAC. But that assumption runs counter to the research on BAC levels.

The National Highway Traffic Safety Administration (NHTSA), in its July 2001 report “Legislative History of .08 Per Se Laws” found that while the risk of being in a crash gradually increases at each BAC level, there was little difference in relative risk for drivers with BAC levels between zero and .05 This risk, however, rises very rapidly after a driver reaches or exceeds .08. This report also states that:

A BAC of .08 is a reasonable level at which to set the illegal limit. A .08 BAC is not typically reached with a couple of beers after work, or a glass or two of wine with dinner. The average 170 pound male would have to consume more than four 12 oz. cans of beer within 1 hour on an empty stomach to reach .08 BAC. The average 137 pound female would need at least three cans of beer in one hour on an empty stomach to reach that level.”

SAMHSA’s survey method, on the other hand, suggests that people who have a glass of wine at dinner are drunk driving if they get behind the wheel afterwards. (It should be noted that a BAC of .05 – or very roughly, the level produced by drinking two standard measures if sober – is favored by many other countries as the legal cut-off point).

Many of the news reports on the SAMHSA study also linked the results to the rate of alcohol-related traffic crashes and fatalities. Yet data from the NHTSA shows that 85% of all alcohol-related traffic fatalities in 2006 involved drivers with a BAC of .08 and higher, and 58% with a BAC of .15% or higher – the so-called incorrigible group of “hardcore drunk drivers” who cause havoc on our roads.

When providing statistics to guide public safety, making such distinctions are important – in this case, it’s the difference between doing something legal and doing something illegal. The upper Midwest may not be off the hook on drink driving for historical and sociological reasons, but it can’t be judged guilty on the basis of SAMHSA’s stats.

Al Gore Trusted More Than the Media on Global Warming – by Climate Experts!

April 24, 2008

We’ve just released the results of our STATS/Harris Interactive survey of climate experts and among the interesting findings (no surprise that there’s little disagreement about the basic fact that yes, the earth is warming and we’re at least partly to blame) is that Al Gore’s movie, An Inconvenient Truth, is rated as more reliable than any media source:

Only 1% of climate scientists rate either broadcast or cable television news about climate change as “very reliable.” Another 31% say broadcast news is “somewhat reliable,” compared to 25% for cable news. (The remainder rate TV news as “not very” or “not at all” reliable.)  Local newspapers are rated as very reliable by 3% and somewhat reliable by 33% of scientists. Even the national press (New York Times, Wall St. Journal etc) is rated as very reliable by only 11%, although another 56% say it is at least somewhat reliable.

Former Vice President Al Gore’s documentary film “An Inconvenient Truth” rates better than any traditional news source, with 26% finding it “very reliable” and 38% as somewhat reliable. Other non-traditional information sources fare poorly: No more than 1% of climate experts rate the doomsday movie “The Day After Tomorrow” or Michael Crichton’s novel “State of Fear” as very reliable.

For more detail, including the results of who’s been pressured to say what by the forces of government, check out the full release here.

We’ve also published a long look into climate modeling: just how reliable are climate models?

Obama Gets Pushed by a Poll

April 14, 2008

Rebecca Goldin Ph.D

Political Intelligence (field reports by reporters from the Boston Globe) stated this morning that people are disagreeing with Obama – at alarming rates. The story draws on a survey conducted by Rasmussen, which found that 56 percent of Americans disagree with Obama about his comments on small-town America. Even among Democrats, the rate of disagreement is 43 percent. On the other hand, among a “plurality of politically liberal voters,” only 33 percent disagree with 46 percent agreeing.

But the poll’s question pushed the answer. It was phrased as follows:

Obama said that in small towns in Pennsylvania, people ‘cling to guns or religion or antipathy to people who aren’t like them or anti-immigrant sentiment or anti-trade sentiment as a way to explain their frustrations.’ Do you agree or disagree?

What respondents didn’t hear was what Obama said before making this statement. The full quote was:

You go into these small towns in Pennsylvania, and like a lot of small towns in the Midwest, the jobs have been gone now for 25 years and nothing’s replaced them. And they fell through the Clinton Administration and the Bush Administration, and each successive administration has said that somehow these communities are going to regenerate and they have not. And it’s not surprising, then, they get bitter, they cling to guns or religion or antipathy to people who aren’t like them or anti-immigrant sentiment or anti-trade sentiment as a way to explain their frustrations.

Consider the difference: in the first context, the person polled is asked whether he/she agrees that people in small towns cling to guns, religion, antipathy to others, or anti-immigration or anti-trade sentiments. In the actual quote, the context is regarding those people in small towns where the “jobs have been gone for 25 years and nothing’s replaced them” and where the communities have not regenerated over the course of successive administrations.

Asking Americans whether they agree or not with the whole quote may well have had a different effect. According to the Rasmussen poll, only about 55 percent of those polled were following the issue “very closely” or “somewhat closely” and a full 15 percent were not following the issue at all. It may well be that almost half probably hadn’t seen the speech or even heard of the controversy, making the wording of Rasmussen’s question even more influential. How would a typical Clinton or McCain supporter have answered this question, given the sparse context? It makes the 56 percent disagreement seem rather modest.

Math with Monty

April 9, 2008

Rebecca Goldin Ph.D

There’s no way of better inspiring people to think about math than to give them a conundrum where the stakes are high. So it is in the Monty Hall Game, which became famous on the program Let’s Make a Deal in the 1980s. The game gets played as follows. There are three doors, numbered 1, 2, and 3. Behind one of them is a car, and behind the other two are goats. First, a player chooses one of three doors, say Door Number 1. The host then reveals one of the other two with a goat behind it, say Door Number 2. Then the player is offered to switch to Door Number 3 – should she switch?

Our intuition may not be our best friend here. Your gut may tell you that by opening a door that has no goat behind it, you have gained no information (you already knew that there was at least one goat behind Door 2 or Door 3). So your chance of winning is just 50/50. But here’s where it gets confusing. Your best strategy depends on how the game really played.

If the rules require the host to open one of the remaining doors with a goat behind it, then you should switch. When you picked Door Number 1, there was a 1/3 chance that your door has the car, and 2/3 chance that the car is behind one of the other two doors. After the host reveals that one of them has a goat, if you switch to the remaining door, you’ll have a 2/3 chance of winning.

On the other hand, if the host is not required to offer a switch, the odds may not be on your side to switch. And depending on what rule he’s following, your chance of winning or not could rise or fall considerably.

Take for example, the case where the host knows there’s a goat behind Door Number 2, and no matter what choice you make, he intends to open that door. So if you choose Door Number 2 right at the beginning, you lose. If you don’t choose it, then he opens Door Number 2 and offers you the chance to switch. Your chance of winning is now 1/2, regardless of whether you switch or not.

On the other hand, the host could be truly mean-spirited. If you choose a wrong door, he plans to open it and show you that you got yourself a goat. If you choose a correct door, you are offered to switch (and even offered money to take it). Now the chance of you winning if you switch has been reduced to zero!

This problem illustrates the importance in mathematics of having a very clearly stated problem. The problem of whether you should switch is not answerable without a clear statement of the host’s strategy.

Recently, the mathematics of this problem has been applied to psychological experiments involving choice rationalization. The New York Times’ John Tierney has done an outstanding job at explaining the mathematical mistake made by some researchers in establishing a baseline for preference while conducting these experiments. The graphics are extremely illustrative, both in establishing how the Monty Hall problem is related, and in how an excellent article about a confusing yet inspiring math brain teaser can be written.

Prosecutors Try to Gag Medical Testimony

April 9, 2008

STATS’ fellow Maia Szalavitz reports on the Huffington Post on a case where prosecutors are trying to get a gag order on an activist group for pain sufferers. It seems the testimony provided by the Pain Relief Network as to the legitimacy of prescribing opioids for chronic pain is proving difficult to deal with in the ongoing prosecution of doctors for drug trafficking.

Another Reason to Focus on the Risks of Cigarettes and Smoking

April 7, 2008

While activists, legislators and journalists spin themselves into a frenzy over unproven, unfounded, hypothetical, or, at worst, minor risks from chemicals in plastics and cosmetics, a new study reminds us that when it comes to infant health, exposure to the 4,000 chemicals in cigarette smoke should be a national priority. As Medical News Today reports, research published in the American Journal of Respiratory Cell and Molecular Biology shows that “exposure to cigarette smoke inhibits innate gene expression and impairs alveolar growth in neonatal mice.”

The results of this study indicate that exposure to CS [cigarette smoke] during the neonatal period inhibits expression of genes involved in innate immunity and mildly impairs postnatal lung growth. These findings may in part explain the increased incidence of respiratory symptoms in infants and children exposed to CS,” write the authors.

What’s remarkable, beyond further confirmation that a cigarette is the most powerful  delivery system for toxic chemicals among consumer products, is that the study is getting little attention from the media. Given the recent feeding frenzy in the press over the risks of Bisphenol A in plastic bottles,  based on one ridiculous study and contradicted by five massive, independent risk assessments spanning Japan, Europe and the U.S., one can only wonder how much attention the activist spin machine would have generated if the study had found similar results for plastic bottles.


Get every new post delivered to your Inbox.

Join 39 other followers