There are two popular ways for measuring the safety benefit of bicycle helmets. One method is to look at hospital admission records, comparing the relative number of helmeted and non-helmeted patients. The use of hospital records is an indirect measure, because researchers don’t have reliable data on the number of helmeted cyclists in the general population. Due to this limitation, researchers guesstimate risk exposure rates, which is difficult.

The other method is to study the effect of mandatory helmet laws. A time-series analysis of crash-data before and after implementation of a helmet law provides a direct measure of helmet effectiveness. This is the preferred method because it covers a much larger population in real-world conditions (without having to infer risk exposure rates). Time-series studies of helmet laws in Australia, Canada, and Spain have found no discernible impact on bicycle safety.

When direct measurements of helmet laws failed to find any safety benefit, that should have ended helmet debates. But like any zombie idea, the helmet issue shambles along. Why is that? Perhaps one reason is the hospital case-control studies that promised huge safety benefit from helmets (as high as 85%). But what is the reason for the huge discrepancy between direct and indirect measurements?

One reason for the discrepancy may be due to a methodological error in the hospital case-control studies. That is according to a new paper, Overestimation of the effectiveness of the bicycle helmet by the use of odds ratiosby Th. Zeegers. It was presented at the 2015 International Cycling Conference held last month in Hanover, Germany.

Zeegers argues that case-control studies overestimate the risk of cycling for the control (i.e. non-helmeted cyclists) thereby exaggerating the benefit of helmets. He then re-analyzed data from three popular helmet studies. After correcting for the error, he found that the supposed benefit of bike helmets completely vanished:

Due to lack of data on exposure rates, odds ratios of helmeted versus unhelmeted cyclists for head injury and other injuries on hospitalized victims are broadly used in case-control studies. A general necessary and sufficient condition can be formulated rigorously, for which odds ratios indeed equal risk ratios. However, this condition is not met in case-control studies on bicycle helmets. As a consequence, the real risk of cycling with a helmet can be underestimated by these studies and therefore the effectiveness of the bicycle helmet can be overestimated. The central point is that a wrong estimate of the risk for non-head injuries (the controls) paradoxically can lead to an overestimation of the usefulness of the helmet in protecting against head injuries.

Three cases could be found in the literature with sufficient data to assess both risk ratios and odds ratios: the Netherlands, Victoria (Australia) and Seattle (U.S.A). In all three cases, the problem of overestimation of the effectiveness of the helmet by using odds ratios did occur. The effect ranges from small (+ 8 % ) to extremely large ( > + 400 %). Contrary to the original claim of these studies, in two out of three cases the risk of getting a head injury proved not to be lower for helmeted cyclists. Moreover, in all three cases the risk of getting a non-head injury proved to be higher for cyclists with a helmet.

It must be concluded that any case-control study in which the control is formed by hospitalized bicyclists is unreliable and likely to overestimate the effectiveness of the bicycle helmet. As a direct consequence, also meta-analyses based on these case-control studies overestimate the effectiveness of the bicycle helmet. Claims on the effectiveness of the bicycle helmet can no longer be supported by these kind of studies. This might explain the discrepancy between case-control studies and other studies, such as time-analysis. It is recommended to use other methods to estimate the risk ratio for the bicycle helmet, along the lines described in this article.

Justice is Blind

Here is another one of those outrageous cases, where a driver can hit and kill a cyclist without consequence:

The felony conviction for an attorney who killed a Chinese tourist in a hit-and-run crash in 2011 was reduced to a misdemeanor by an Alameda County judge on Friday over “strenuous objection” by prosecutors, according to the district attorney’s office.

Hayward Judge Michael Gaffey also changed the terms of the sentence he handed down to Spencer Freeman Smith just two weeks ago, much to the chagrin of an American friend of the man Smith killed.

“Obviously, I am not a judge or a lawyer but, for me, using common sense, it’s an outrageous decision,” said Dr. Arnold Owens of Oakland. “Everything has gone so much in favor of the defendant, it seems like some shenanigans are going on.”

Smith, 36, was living in San Ramon working as a San Francisco labor attorney on March 12, 2012 when, after a night of drinking with a paralegal from his firm, he fatally struck 57-year-old Chinese financial adviser Bo Hu on Dougherty Road in Dublin, prosecutors say. Hu was in the country for his fiancee’s relative’s graduation and was killed while he was walking a bicycle.

Smith did not stop or even brake at the scene and was apprehended by Dublin police investigators after they matched broken vehicle parts left at the scene to his brand new Mercedes-Benz sedan.

Oh, did I mention that the driver is blind in one eye? Incredibly, that fact worked in his favor:

“Anyone driving down that dark roadway could have hit Mr. Hu; it just happened to be Mr. Smith,” he said. “The judge recognized that this was a tragic accident and Mr. Smith was in a more vulnerable situation because he is blind in his right eye.”

The Judge did not even take away Smith’s driving license. Though I suppose the real question is why the California DMV gives out driving licenses to people blind in one eye.

The Sierra Club has spent considerable effort fighting against development in San Francisco. Most recently, they endorsed Measure I, which would impose a housing moratorium in the Mission District.

And guess what happens when development is curtailed:

After 124 years in San Francisco, the Sierra Club is moving its headquarters across the Bay to Oakland because of rising rents in The City. The nonprofit on Thursday announced its headquarters will move from its current site at 85 2nd St. in San Francisco to 2101 Webster St. in Oakland in May 2016, after learning the group faced an annual rent hike of more than $1.5 million, said John Rizzo, political chair of the club’s San Francisco Bay Chapter.

The National Troupe of Silly Bureaucrats (NTSB) wants to downgrade Washington Metro into a commuter-rail service. They are recommending that Metro be brought under FRA regulation:

Metro’s safety problems are so severe and persistent that federal officials should take a much stronger role in monitoring the subway system: reclassifying it as a commuter railroad so the transit agency can be subject to tougher regulations and penalties, the National Transportation Safety Board said Wednesday.

In an “urgent” recommendation to Transportation Secretary Anthony Foxx, the safety board’s chairman, Christopher A. Hart, cited years of “repeated and ongoing deficiencies” in Metro and said the current oversight process, involving the Federal Transit Administration, is inadequate and bound to keep failing.

Hart urged Foxx to ask Congress for the authority to reclassify Metro as a commuter railroad, which would remove the subway from the FTA’s safety oversight and place it under the “robust inspection, oversight, regulatory, and enforcement authority” of the larger, more powerful Federal Railroad Administration.

As if Washington Metro didn’t have enough problems.

Once it becomes an FRA-regulated railroad, Metro would need waivers just to run lightweight equipment. Metro would have to deal with all the ridiculous operating rules, like mandatory brake-checks at the start of reach run. The costs would be staggering.

He [Hart] also mentioned the Aug. 6 derailment of a train — which was not carrying passengers — between the Federal Triangle and Smithsonian stations.

Right…because the FRA has done such a fantastic job of preventing derailments on MetroNorth and Amtrak.

The Federal Railroad Administration oversees “heavy” systems — freight and commuter lines, such as MARC and VRE, as well as Amtrak. But the closest system to an urban subway that the administration oversees is the Port Authority Trans-Hudson (PATH) line, a 14-mile rapid transit link between New Jersey and New York. About half of PATH’s tracks are underground.

In its recommendation, the NTSB uses PATH as the model for FRA regulation of Metro. But as I pointed out last year, FRA regulation of PATH has been an unmitigated disaster. FRA rules increase PATH operating costs by a factor of 3 — and haven’t done anything to improve safety.

Blame the victim

A driver illegally crosses a double yellow line to pass, and fatally hits a bicyclist coming the other direction. Of course, the CHP says the driver was not at fault:

The accident unfolded after a vehicle moved toward the center of the road to pass one of the racers, CHP Sgt. Andy Hill said. As the driver moved to pass, she failed to see a second racer, riding near the middle of the road in the opposite direction, Hill said. The car was traveling about 35 mph and the bicyclist about 30 mph when they collided, according to the CHP.

“Unfortunately the (victim) was not riding on the far right side of the lane. He was riding in the middle of the road where the yellow line is,” Hill said. Hill said both parties contributed to the collision. Cyclists are required to ride as far to the right as possible, he said, while cars are required to have appropriate space before passing. Authorities have not identified the driver, a 35-year-old woman from Esparto. No charges or arrests have been made.

It is disappointing (but not all that surprising) that the CHP misinterprets both the 3-foot passing law and CVC 21202. CVC 21202 permits cyclists to move to the center of the lane for any number of reasons: to avoid hazards, or when the lane is substandard width. As in so many car-bike collisions, the police in this case found creative legal interpretations to absolve a driver of her dangerous and illegal behavior.

PTC Deadline Excuses


On May 8, 2011, a PATH train overran the platform Hoboken, striking the bumping post at the end of the track. Of the 70 passengers on-board, 30 passengers plus two crewmembers were hospitalized with non-life-threatening injuries. An NTSB investigation concluded that PTC would have prevented the accident:

PATH has submitted its PTC implementation plan to the FRA, and the FRA has approved the plan. The proposed PATH PTC system would enforce an absolute stop for trains approaching the platforms at Hoboken station. The NTSB, therefore, concludes that the PTC system proposed for implementation by PATH would have automatically alerted the engineer to the train’s excessive speed; and if the brakes were not applied, while operating in automatic mode or manual mode, the PTC system would have automatically applied the brakes to stop the train and prevent the collision.

PATH suffered a similar kind of accident in 2009 at Journal Square.

It has been more than four years since the Hoboken crash, which is sufficient time to install the PTC system. The Port Authority, however, is dragging its feet:

PATH officials have joined officials from 21 passenger and commuter railroads and seven freight railroads asking the U.S. Senate to extend a Dec. 31 deadline to implement an automatic speed control system.

PATH officials warned that they could be forced to reduce or suspend service if the deadline isn’t changed and the Federal Railroad Administration fines railroads that haven’t complied.

“The delay in meeting the deadline in no way, shape or form jeopardizes the safety and or quality of service that PATH provides to 265,000 daily riders,” said Michael P. Marino, PATH director and general manager in a Sept. 17 letter to a U.S.senate committee.

Since the passage of a 2008 law that mandates PTC, PATH has “zero accidents” that would have been preventable if PTC were installed, Marino said.

Not only are PATH officials endangering riders, they are also lying to Congress.

The helmet fear-mongers go full-retard:

For the past decade, we’ve drilled into children that when they ride a bike, they need to wear a helmet. Now scientists say it may be too late: Tricycle riders should be wearing them, too.

Using data collected from 100 emergency rooms for the National Electronic Injury Surveillance System, researchers found that boys are more likely than girls to turn up in the emergency room. Two-year-olds seem to have the most accidents, although there were tricycle injuries for children up to age 7. The most common broken bone was the elbow and the most common injury overall was a cut to the face.

In addition to helmets, the authors suggest kids wear elbow pads, and that parents supervise their children while they ride.

Even better, just make them wear bubble-wrap.



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