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Im not sure it really means Forrester was entirely wrong - it certainly shows street riding in many conditions to be safer than side MUP riding, which to me was the key Forrester take away. Even a bike only trail is not as safe as a major street WHEN there are no parked cars and there is a designated shared lane. I don't think those results confirm at all the POV that streets in general are dangerous for cyclists. It only disputes the more extreme form of VC, the assertion that integrated riding on streets is better even than well designed bike lanes, and that the the exact conditions of a street shouldn't matter to the confident cyclist.

Unfortunately, the "Forrester was wrong" article is paywalled, and everything available online just goes back to the abstract -- which contains nothing about the methodology used to measure risk.

I've learned to be very skeptical of any study that purports to show anything about bicycle safety. Bicycle accidents are so rare that there just isn't a whole lot of data out there.

The abstract does show confidence intervals on the point estimates of the accident rates. They overlap, suggesting the results are statistically insignificant.

What cycletrack did they use in the study? There seems to have been a spate of accidents on the 15th Street and Penn Ave. cyclotracks here due to turning vehicles. I certainly avoid them as I think they are inherently dangerous as designed.

If the study is really all it's cracked up to be, then it is pretty interesting. The methodology certainly sounds clever, although I'd like to see it reviewed by someone reasonably even-handed who is less gung-ho about dedicated infrastructure (John Allen, say) to see if he can poke any substantive holes in it.

I agree though with the first comment above that this is hardly rejecting all aspects of VC, although it doesn't square with Forester's extreme version of it. Note that, according to this study, major streets with no bike lanes and no parked cars are equally safe/dangerous as bike-only paths, and much LESS dangerous than multi-use paths like the CCT or MVT. Indeed, even though people love them, MUPs are more dangerous than any of the routes except for major streets with no bike infrastructure and no parked cars!

If you excluded cycletracks from that nice plot, I'm not sure what conclusion you would draw, except that parked cars are really dangerous. I wonder what fraction of the injuries they studied were caused by dooring.

One final note on Forester: He gets a lot of grief for being so anti-infrastructure, and maybe rightfully so. But the context of his original work was the 1970s, when transportation departments the world over were trying to force bicyclists onto crappy dangerous sidepaths and make it illegal for them to use the road. If I had been trying to cycle during the '70s, I'd probably be pretty vehement about my pro-road-use position too.

I don't see how Bethesda "earned" its rating. If it weren't for the two trails mentioned, the rest of the immediate built up areas are not exactly bike friendly. I generally respect those ratings but really the current on street inrastructue is weak at best.

The diagram is slightly modified, but from “Bicyclists’ Injuries and the Cycling Environment”: http://cyclingincities.spph.ubc.ca/injuries/the-bice-study/. From that page: "The study took place in Toronto and Vancouver between May 2008 and November 2009." I don't know either place, but the cycletracks there would be used. Interestingly, the included diagram offers scale that the UBC diagram does not. I wonder if the scale is appropriate. Of course, I don't have access to the original paper. It might say so there.

It seems to me the plot is telling us people are poor judges of risk. Not all preferred routes were safer than routes shared with motor vehicles. If you were to flatten the plot, you would end up with major streets being a good bit safer than multi-use paths. In some cases, anyway. I guess that makes me quibble with write-up's contention that "Preferences and safety largely agree." They equivocate on the matter.

I am curious, what makes a "cycle track" different from "bike only"?

Hobby horse: why do planners insist on mushing all cycling with recreational pursuits? That kind of planning is what leads to grumpy articles here (and elsewhere) about the federal transportation funding for cycling that got turned down a month ago, or so. Maybe money-directors make the assumption that more cycling is recreational (might be). I imagine as argument that there are a lot of kids that go out with Mom and Dad that aren't going anywhere in particular. Perhaps it is assumed the relative proportion of people that are cycling to get to work or the store is rather small. I can see the argument working, but I can't see the data. Is there data? Maybe I should be honest: I don't really go looking for that kind of information and if it isn't on the surface, I probably miss it. This study says that 74% of the trips were utilitarian and that is contrary to the imaginary argument I've made.

The conclusion is thoroughly appropriate: it IS safety information that is worth something to road planners.

I would think it would be of use to find what makes those different routes more or less safe.

I would, at a glance, it has something to do with differences in speed of various modes of transportation permitted on the route, signage and total volume?

Maybe a plot with those variables as functions of relative safety would be an interesting plot.

I find myself wondering if the preference versus safety plot treats those wretched sidepaths next to major roads as if they are the equivalent to MUPs, such as the Mt Vernon Trail. If not, this makes a strong argument for re-thinking and improving road/trail intersections.

The "No U Turns" sign on Pennsylvania Avenue didn't block the cyclists' view, but rather the entire westbound bike lane.

"I am curious, what makes a "cycle track" different from "bike only"?"

I guess position relative to the travel lanes, and turn lanes - I would guess the bike only is similar to a MUP but with pedestrians excluded - but still with poor positioning at intersections vs a cycle track.

WRT to recreational = I think there are huge grey areas - sure if someone drives to the W&OD, and rides 10 miles and back for exercise, thats recreational. But if I break for lunch, how do we seperate that from biking TO lunch? If I ride from home to the W&OD, is that any less transportation to get to my recreation than if I had ridden or driven to a gym?

"I find myself wondering if the preference versus safety plot treats those wretched sidepaths next to major roads as if they are the equivalent to MUPs, such as the Mt Vernon Trail." Im sure they did not have enough data to break the bike facilities into even finer categories than they did. Or roads for that matter.

I bought the paper from the American Journal of Public Health for $22. Worth every penny. It's a well researched and structured study in my opinion.

"Still, all in all, it was probably worth it."

I'm curious if this is serious or sarcastic... I can see it from different sides. He inspired many, created a foundation, experienced amazing wins... and even if he won through cheating, apparently lots of others were cheating too, so he still outperformed and that's worthy of respect... but also lied repeatedly, brought shame to his team and sport, set a dangerous precedent for other cyclists and athletes.

The outliers in preference v safety are MUP and local streets. This could be due to (a) poor perception of risk (b) favoring factors other than risk (I'd rather ride along a wooded path than in traffic) or (c) failure to account for seriousness of injury in the study. When assessing risk, we don't consider merely the likelihood of injury, but also its seriousness. I'd rather 10 scrape and falls to one broken leg. The study did not categorize for seriousness of injury and excluded those with the most serious injuries.

This is not to say that the study is bad, merely that more research is needed and that caution is required in interpreting the results.

Also, the signs on Penn were in the middle of the bike lane and, while they did block sightlines, that is a safety issue. "Blocking the view" sounds aesthetic.

This quote from the summary makes me dubious: "The most commonly observed route type was major streets with parked cars and no bike infrastructure. It had the highest risk. "

Risk is events divided by exposure. There's no talk of what the denominator is -- how are they measuring exposure?

The study finds that "Major street with parked cars and bike lane" is more dangerous than "Major street with no parked cars and shared lane" or "Major street with no parked cars". In other words, as Keroicap pointed out, parked cars are a hazard to bicyclists.

A 2011 study by the same authors looking into the methodolgy they applied:

And another study by a couple of these authors from <2010, looking into preferences.

tim h,

I was serious.

Let's say that he cheated and that without cheating his career would have been less spectacular. More like Levi Leipheimer's let's say. Cheating allowed him to gain all the benefits of incredible success. He made tons of money. He garnered fame. He got to stand on the top of the podium (and they can't take those experiencs away from him). He got to sleep with famous and beautiful women. He got to mountain bike with the President. He got to host SNL. The cheating opened so many doors for him that would have never been opened otherwise. Who cares if they're now closed? Whatever he gives up over the rest of his career and life for all that he got over the last 13 years it will probably be a very good trade. He's still famous. He can still trade on that and he will probably continue to make more money than Levi (or someone else who was clean) and sleep with women attracted to fame. Considering he won't go to prison of lose any of his money, he's done very well for himself.

On Sunday evening around dusk (6:40-6:45 PM) I was driving home and there was a cyclist down on Southbound Beach Drive, just below the light at Tilden / Park. The cyclist was being well attended to medically and from the placement of bike & cars I'd guess if the vehicle was involved, it was from behind. Any news?

As Jack points out, there is control for the denominator.

Each injured person had to map their route, which would encompass many types of roads, paths, etc (creating the denominators for each person) and then where they got hit. Comparing these across people gives an idea of risk.

This approach supplements other sort of studies which just count number of riders per route versus number of accidents, which cannot correct for the different type of riders on the different routes.

Won't lose any of his money?

Texas insurance company SCA Promotions confirmed it would seek to recoup at least $7.5 million paid out in bonuses to Armstrong under a contract with Tailwind Sports, owner of the American’s former US Postal Service team.

Yeah, they're not guaranteed to win, but still.

I never liked Lance, but respected his achievements and think that the treatment of Lance is disgraceful.

Everyone seemed willing to ignore his many flaws, and suggestions of doping, but now they are shocked, SHOCKED that he was doping and are throwing him under the bus to make themselves look moral. All those advertisers made money off Lance being associated with their product: are they going to return THAT to the consumers who bought the products? Are consumers really going to complain about the products now that Lance is judged guilty? Of course not. I think that losing all 7 TDF titles is enough.

Wash, your comment sounds eerily like this one:

Someone posted to YouTube a 15 minute video of a roundabout in Netherlands and I found myself watching (yes, watching traffic) the interaction between autos and the bike path and noted that there was a carlength between the road's entrance to the roundabout and the cyclepath's roundabout crossing the intersecting road. That allowed a car to pull ahead of the cyclepath while awaiting an opening into the roundabout. -- but no more than a single car. It would still get blocked by a bus.

I compared this to common sidewalks and bike lanes here and thought, well, is that the difference? As we know, a driver waiting for an opening in traffic will pull into the sidewalk crossing and maybe into the bike lane to ensure clear visibility of the auto traffic and readiness to enter the traffic lane when possible.

Now, cycletracks are in the middle of the road and therefore presumably visible (not that the traffic on the cycle track on Pennsylvania Ave is very visible!), but smaller traffic lanes that are on the side of the road like Rock Creek trail are not - does that make drivers less able to see the traffic on those trails? (I think so, hence I prefer on-road travel)

I drove Democracy Blvd down by Seven Locks a few days ago and noticed that the MUP parallel was set rather far from the road. What if the stop signs and the stop line for the auto traffic were even with the trail traffic? If I might day dream a little, what about a stop sign for auto traffic at crossings like that for the Dr. Gridlock column a few weeks ago?



Curious what you think of folks like Hamilton, Landis, and Ullrich. The guys whose lives were destroyed, but didn't have the benefit of protection from the sport's ruling body.

1. The doping law was based on blood levels. Those were the rules, and Lance met the rules. Arbitary: perhaps, but no system of laws can capture moral distinctions, so we settle for specific threshold questions. E.g. it doesnt matter if you want to kill someone, only whether you acted upon it.

The UCI knew that doping was going on. They decided that the test was blood levels. Lance met that test every time. The others did not.

2. At the same time, I think it is completely disingenous for people to pile on Landis et al. I agree that they should be disqualified for their win, but lifetime bans etc are too far. They are still great athletes, albeit with the aid of drugs.

UCI is expunging its moral demons by blaming the riders. "Just say no to drugs" hasnt worked so well in general society, and it seems not to work in cycling.

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