Saturday, March 3, 2007

Speed doesn't matter...or so they say.

The enthusiast media have all but "proven" that raising speed limits over the last two decades in the US has had no effect on fatality rates. They like to cite the gradually declining overall death rate, that is, the number of fatalities per 100 million miles traveled. (The death rate increased slightly in 2006 compared to the prior year.) But looking at overall death rates is inherently flawed, because these include fatalities on ALL roads, regardless of whether speed limits have been changed.

There is ample evidence that higher speed limits increase fatalities on roads where such limits have been changed compared to similar roads for which speed limits were not changed.

The problem is the enthusiast media refuse to accept the studies, done by respected organizations like the National Academy of Sciences, NHTSA, the Insurance Institute for Highway Safety, and an academic group in Australia (which studied US roads). Some of these studies have been published in well-regarded peer-reviewed journals like Accident Analysis and Prevention and in SAE papers.

So "experts" like Brock Yates, Pat Bedard, and the National Motorists Association try with all their might to debunk such studies. One technique they use is the "Big Lie." That is, they repeat an untruth over and over to the point that the average reader will believe it's true. And unfortunately, the average enthusiast WANTS to believe it's true -- after all, fast driving is fun, and why spoil the fun with facts?

One of the worst of the Big Lies goes like this: The IIHS is supported by insurance companies. Insurance companies want lower speed limits so more drivers can be ticketed and therefore can be surcharged on their insurance policies. Thus, the insurance companies can earn more profits.

Well, the IIHS has ABSOLUTELY NOTHING to do with setting insurance rates. This is handled by each company using actuarial statistics. Proposed rate increases or decreases must be approved by state insurance regulators. Even IIHS's crash tests don't directly affect rates. Why not? Because the severe tests the IIHS conducts are relatively rare events, and the bulk of insurance payouts goes to repair cars in fender benders and medical payments for minor injuries like whiplash.

Also, the crash tests don't reveal anything about how or where or by whom the cars are driven, which obviously also affect crash rates in the real world. The purpose of the tests is to raise the bar on crashworthiness so all cars do a better job of protecting their occupants in severe crashes. The end result, hopefully, will be more lives saved and injuries reduced.

And in fact, studies conducted thus far have indicated that cars with better frontal crashworthiness do protect their own occupants better in real-world frontal crashes. It's too early yet to tell if the same is true for side-impact crashes, since the IIHS just started conducting these in 2003.

To my knowledge, nothing written by Yates, Bedard, or the National Motorists Association has ever been published in a peer-reviewed journal.

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