Industrialized Cyclist Notepad


Thompson Rivara Thompson ’96

Thompson, Rivara and Thompson M.D.s, “Effectiveness of Bicycle Safety Helmets in Preventing Head Injuries,” JAMA, 1996.

RT96tablew

This is probably the most cited of all helmet studies. It appeared at a time when the CPSC was considering the possibility of making new standards for little kids’ helmets. On one side of the discussion, engineers and advocates who thought child and toddler helmets should be made softer to protects kids from the type of head injuries they are most likely to suffer while bicycling. On the other side, helmet company reps who argued that kids didn’t need new standards or softer helmets.

Thompson, Rivara and Thompson’s “Effectiveness of Bicycle Safety Helmets in Preventing Head Injuries” came along just in time to lend the industry some apparent scientific legitimacy to their argument.

The study concludes like this: “Based on our study, changes in helmet certification standards or the design of helmets particularly for younger age groups are less likely to result in major benefit.” The mention of kids’ helmet standards–“particularly for younger age groups…”–comes out of the blue at the end of the paper.

This is quite strange because, earlier in the document, the authors revealed that the study, which included over 3,000 crashed cyclists, included only one helmeted brain-injured subject under 6 years of age. Because of this almost total lack of data, the authors admit that their study cannot estimate any protective effect of helmets for this age group.

Hmm. But in the conclusion, which is the only part of the privately held document that journalists or 99% of the public will ever read, the authors do just that. They claim that helmets give the same protective benefit “to cyclists of all ages…” And then they go out of their way to say that bit about little kids not needing better helmet standards.

I don’t know about you, but I think it’s very interesting that the particular age group that receives the most attention in the conclusion, is the one that received the least attention when collecting data. This seems to be a really smarmy piece of work.

See industrializedcyclist.com and Family Biking: The Parent’s Guide to Safe Cycling for more on kids’ helmet standards.



More Misplaced Efforts on “Bike Safety”

Capt. Jack Danilecki of the Boston police, former commander of the tactical bicycle unit, said that five cyclists were killed in Boston last year. Police are taking an initial step to address the problem by issuing reminders — in the form of $20 tickets — to cyclists who run red lights and stop signs that they are legally bound to obey the rules of the road.

via How to protect cyclists | Harvard Gazette.



The God that failed

Pinka Chatterji and Sara Markowitz, “Effects of Bicycle Helmet Laws on Children’s Injuries.” NBER Working Paper No. 18773. February 2013. JEL No. I0,K0

ABSTRACT
Cycling is popular among children, but results in thousands of injuries annually. In recent years, many states and localities have enacted bicycle helmet laws. We examine direct and indirect effects of these laws on injuries. Using hospital-level panel data and triple difference models, we find helmet laws are associated with reductions in bicycle-related head injuries among children. However, laws also are associated with decreases in non-head cycling injuries, as well as increases in head injuries from other wheeled sports. Thus, the observed reduction in bicycle-related head injuries may be due to reductions in bicycle riding induced by the laws.

Pinka Chatterji
State University of New York at Albany Economics Department

Sara Markowitz
Department of Economics Emory University

The auto industry loves mandatory helmet laws.



Maryland House Bill 339

Would require helmets for adults on bicycles.

HOUSE BILL 339 (pdf).



Negativity Dominance

This article makes a good point or two.

I’d just point out a minor issue. If fatalities-per-trip is falling, that might not mean that cycling is safer. It might just mean people are making more frequent, shorter trips. The metric you want is (if you want to use fatalities) fatalities per hour of bike use. But this is an even more elusive figure which ultimately relies on self-reported surveys of bike use — allowing us to fill in the blanks (erroneously) with our emotions as the article mentions. Furthermore, injuries might be higher even if fatalities are lower.

If all cyclists suddenly started following the letter of the law, cyclists would be much more in the way, and negative emotions toward cyclists would grow, not disappear. But that’s just a theory.

Cyclists are annoying: Why you think they’re a menace on two wheels. – Slate Magazine.



Former Denver Councilman and mayoral candidate Linkhart hit by truck on Bike to Work Day

He was my favorite mayoral candidate. He has almost no TV charisma, which is a major plus for a public official. He would have made a fine mayor. He liked libraries.

Fortunately, he’s fine, but the incident did prompt a conversation between council members and the mayor about road safety regulations and the interactions between cyclists and vehicles.

…During which, of course, scofflaw bicyclists somehow came out the villains, and education and/or reprogramming of scofflaw bicyclists was re-hurled to the tippy top of the bike safety priority list. This even though Linkhart’s crash (1) did not involve a scofflaw bicyclist and (2) car-bike crashes involving adult bicyclists typically do not. The most likely scenario for an adult bicyclist is to be caught out by another road user’s looked-but-failed-to-see error while riding lawfully. But hey, we’ve all seen bicyclists run lights right? People like Mayor Hancock make no attempt to understand the truth about urban cycling safety. Why bother — everyone knows it’s “common sense.” Common sense is good politics. Let’s not let any facts get in the way of our “common sense” about bicycle safety.

According to Linkhart, he was heading west on 23rd Avenue — on a bike route — approaching Downing Street when a pickup truck went to make a left turn and collided with him.

“I was going straight. He turned left in front of me, and…hit me across the side, and I fell down,” Linkhart recalls.

… Linkhart was scraped up badly, his bike got a bit bent and he had to get several stitches in his leg.

“I kinda went flying,” he said. “I kind of plowed into the sidewalk. I had a helmet, which didn’t help.”

Linkhart, going straight, had the right of way over the pickup truck, which was turning left.

23rd and Downing is classic left cross territory. I’ve been through that intersection a hundred times. Got to ‘keep your head on a swivel’ so to speak.

via Westword Doug Linkhart, ex-councilman, hit while cycling to Bike To Work Day event – Denver News – The Latest Word.



Fort Worth mayor wipes out hard in bike wreck

Joining former Colorado Governor Bill Ritter in the annals of history.

What started as a routine Saturday morning bicycle ride for Fort Worth Mayor Betsy Price ended with a broken collar bone, a concussion and some scrapes.

Despite her injuries, Price is in good spirits and still has a sense of humor, said Jason Lamers, chief of staff for Price and the City Council.

via Fort Worth mayor breaks collar bone, suffers concussion in bike crash | Fort Worth | New….