Studying not believing


Soft landing zones are even better than helmets/Craig Medred photo

Leave it to science to confuse you with data about what you just know is absolute fact.

This time it regards the claim bike helmets save lives. Every cyclist reading this falls into one of two groups:

  • The group which has had a bad crash and is convinced that “but for that helmet, I wouldn’t be alive today.”
  • Or the group who knows someone in the previous group who proselytizes for helmets because “but for that helmet, I wouldn’t be alive today.”

Many non-cycling friends of cyclists would also fit the latter category. Given that cyclists are encouraged to wear helmets “because it could save your life,” it’s only logical to assume in the wake of a crash that the helmet worked.

And it could well be true that it did. The person making the claim could really be one for whom the helmet was a life saver.

But scientists in California went looking for objective data on how much of a difference helmets truly make, and what they discovered proved surprising.

After combing through the medical files of 1,454 people treated for injuries after bicycle accidents in the Los Angeles area, this is what they found, according to paper published in January in the International Journal of Advanced Research in Orthopaedics:

“Overall, 292 patients had severe trauma. Significant head trauma was diagnosed in 142 patients (10 percent). The prevalence of significant head trauma was 35 percent in the group of patients with helmets and 34 percent in the group without helmets. It should also be noted that the prevalence of all significant trauma was 26 percent in the group of patients with helmets and 20 percent in the group without helmets.”

The small difference between head trauma in the helmeted and unhelmeted groups is statistically meaningless. Much the same could be said of the percentage difference between the significant trauma suffered by helmeted and unhelmeted riders, though the difference there is approaching significance.

That could be due to a couple of things. Helmets could be encouraging cyclists to ride faster and/or take more risks, or helmets could be altering the behavior of motorists.

Other studies, Dr. C. Thomas Vangsness Jr. and colleagues note in their Los Angeles examination, “found that when driving near a helmeted bicyclist, drivers tend to drive closer than when driving near a non-helmeted bicyclist. This may have to do with the driver believing a bicyclist is more protected when wearing a helmet and may lead to more traumatic injuries for helmeted cyclists.”

The real issue

But the key part of the study might have little to do with the hot-button subject of helmets.

“The medical literature is (already) divided on the efficacy of helmet efficacy,” the authors note. Even if the self-appointed safety police of modern society are prone to see helmets as the simple solution to saving lives, the belief in helmets as the silver bullet has been questioned by some previous studies.

Which is not to say a helmet won’t help you. Helmets do offer some protection in crashes. There is no denying that.

As Alyssa DeMarco and Benjamin Elkin observe at MEA Forensic, an engineering firm involved in safety testing, “helmets can attenuate impacts and reduce the forces transmitted to the skull and brain during an impact. Helmets, however, do not guarantee protection in all impact conditions and some helmets provide better injury protection than others.”

The best advise for cyclists might be that now given to downhill skiers, who are involved in a sport where helmets have only recently become regular gear: Wear a helmet, but ski or snowboard like you’re not wearing it. 

That’s advice easier to give than to practice, and it is more applicable to skiing – where dangers are fixed – than cycling where the biggest dangers are moving.

“The most common mechanism of injury was collision with a motor vehicle without being thrown off (44 percent) followed by collision with a motor vehicle and subsequently being thrown off (26 percent),” the California researchers reported.

In other words, 70 percent of the injuries came from collisions between motor vehicles and bikes.

The study did not attempt to quantify the number of the cyclists on the roads in Los Angeles, but did note that “bus ridership has been associated with increased bicycle use. (And) Los Angeles is different from all previously studied major urban areas because of its large bus ridership and its remarkable road traffic congestion.

“The seriousness of the issue of bicycling injuries has been underscored by the recent implementation of legislation that mandates drivers in the state of California to maintain a distance of at least three feet from bicyclists on the road.”

Bicycling magazine last year declared “Los Angeles Is the Worst Biking City in America.” 

“In the past five years alone, more than 180 riders in the metropolitan area have been killed by people driving motor vehicles,” Peter Flax wrote in the story below that headline. “During the last three years that national crash data has been compiled (2014-2016), only three U.S. states have seen more cyclist fatalities than just L.A. County—Florida, New York, and California as a whole.”

The city has begun to take notice. CBS Los Angeles noted an effort to upgrade and improve city bike lanes after paying “out more than $19 million in lawsuits to settle cases involving cyclists injured or killed on city streets” in 2017.

The authors of the bike helmet study, which used data gathered at the Los Angeles County-USC Medical Center, said they were in a unique environment for such a study.

“This study differed from the previous literature as it sought to
investigate variables of bicycle injuries specifically in one of the world’s busiest emergency rooms,” the authors wrote.

Their main finding was not surprising:  bike accidents caused a lot of broken bones.

Of the 1454 bicycle injuries in the LAC+USC registry we reviewed, 78 percent had fractures,” the wrote. “The 1140 fractures, including bones of the upper and lower extremities, are consistent with a previous study….

“Cycling on the shared road has previously been found to increase the
chances of injury….In Hong Kong, cycling injuries on public roads (with cars) were more severe than those occurring on cycling tracks.”

The study could be read to indicate that where you ride has a lot more to do with the likelihood of a suffering a serious injury than what you wear on your head.

The wild cards

What the study doesn’t include is much in the way of demographics to define those seriously injured in bicycle accidents other than to note a quarter were age 18 or younger.

But the overall low use of helmets – 14 percent – among the almost 1,500 injured cyclists might indicate a sample weighted toward lower-income Los Angeles residents who tend to live in neighborhoods with lower quality cycling infrastruture and other issues, as Bicycling writer Dan Koeppel pointed out in a lengthy, 2015 story about pedaling the city’s poor neighborhoods.

Nationally, it has been estimated that about 30 percent of cyclists always wear helmets and another 15 percent occasionally do.

A 2012 study in Winnipeg, Mantibou, Canada, found helmet use above 50 percent in one of the city’s ritzier suberbs. Use fell to half that in poor neighborhoods.

Income could, as in many previous studies, be skewing the data in one direction or another, although a lot of other studies have found helmets in general over-rated.

Among those who can afford resort skiing or snowboarding, the National Ski Areas Association (NSAA) now reports 80 percent wear helmets. Almost 60 percent of resort skiers are reported to have incomes of $100,000 or more. 

The huge increase in ski helmet use since the 1980s has lowered the number of head injuries among this group by only about about 1 percentage point, according to NSAA data. Experts have attributed the lack of a more significant reduction to helmets encouraging skiers to ski more aggressively.

The average fatality on the slopes in Colorado is an experienced, 37-year-old “male skier wearing a helmet and (who) loses control on an intermediate, groomed run and hits a tree,” according to the University of Colorado.

“Helmets protect at lower speeds (less than 12 mph) and skiers or snowboarders are typically hitting trees at 25-40 mph.”

Ski helmets are sturdier than bike helmets and less debated these days, possibly because they’ve taken the place of the wool hat for keeping heads warm.  And they are an upgrade on the wool hat; many now come outfitted with first-class sounds systems for listening to your favorite music. 

Criticism of bike helmets has focused largely on the idea that best way to make cycling safer is to put more cyclists  on the roads – so drivers are constantly aware of unprotected road users  – than to put helmets on their heads – which still leaves their bodies exposed to crushing blows from cars.

Helmet critics love to point to the Netherlands where bikes are everywhere, helmets are almost nowhere, and the injury rate is among the lowest in the world.

The new study out of California is sure to stir more debate.


















38 replies »

  1. I’m surprised that nobody has brought up the fact that the numbers in the initial study strongly suggest that unhelmeted cyclists didn’t even get counted because they never made it into the ER because they had already died in the field. This is a very common bias in these types of studies using emergency room data.

    • that’s certainly possible. but if one believes the data from the League of American Bicyclists, a reputable group, it could also be the opposite:

      “Among the fatalities tracked by Every Bicyclist Counts, only 150 of the 633 reported fatalities included information on whether the cyclist was wearing a helmet. In the majority — 83 or 57% — of those fatalities the cyclist was wearing a helmet.”

      if the national data applies to California, it could be that 57 percent of the cyclists dead in the field were wearing a helmet, in which case there is a bias in the opposite direction.

      there is a lot of sloppy reporting of cyclist deaths as you might have noted from the lack of data the league found on helmet/no helmet. there is also a lot of U.S. bias toward the idea that simply wearing a helmet will make something safe, although this doesn’t appear to apply to motor vehicles even though 52 percent of the fatalities in those crashes come from head injuries.

      if one actually looks at the data, the argument for mandatory helmets for drivers of and passengers in motor vehicles actually appears a little stronger than that for cyclists, in part because motorists could wear large, heavy truly effective helmets like race car drivers wear. those helmets, though a true safety aid, are unfortunately impractical for cyclists.

      • Thank you for taking the time to thoughtfully consider and respond to my comment with a carefully constructed counter argument. Informed, measures dialogue seems more important than ever. This is a great blog.

  2. Here is a video done by my son while powder skiing at Eaglecrest a few years ago:
    This gives an idea of how skiers can come into contact with trees outside of groomed areas (which is how Sony Bono died). Anyone not wearing a helmet doing such is taking a huge risk but I’ll also say that my son’s opinion is that the chance of hitting arms and shoulders is greater than the head.
    My earlier comment about Colorado ski areas placing trees in the groomed runs was clearly a joke but those trees alongside those groomed runs make for some abrupt stops should someone hit them-they are not cushioned, like the metal supports for the chairlifts and a helmet may not be enough protection (depending on speed). I just got back from a few runs myself @ Eaglecrest with a helmet.

    • While on ski videos, here is probably the greatest upset in Olympic alpine skiing that happened last year in the Downhill:
      Note that she and all competitors are wearing helmets and for Steve-O, note the landing Ledeka makes in her last jump before finishing. Not the greatest jump and she no doubt lost time on it but she did land it (with a helmet, no less).
      Like I said earlier Steve-O, your problem was not the helmet but the landing on your jump.

      • No Bill, my problem is that I’m not an Olympic athlete. I’m not sure what your problem is, but it’s clear that you have one. I’ve heard that repeated brain injury causes short tempers and the inability to control your emotions, perhaps you’ve taken a few too many spills wearing a helmet that doesn’t provide adequate protection?

      • Steve-O, Dick Nixon used to make jokes about Gerald Ford, saying that he played too many football games without his helmet. Well, in that same grain it appears that you’ve done too much skiing without yours.

      • I’ll play the part of Gerald Ford for you, but I guess that makes you just another crooked Dick?

    • Bill,
      Thanks for sharing that video.
      Eaglecrest looks like it has some nice terrain.
      At the end of your son’s video where that pillow of snow releases and he takes a ride, well those situations are out of our personal control.
      I was going to say, we never know when the slope may slide and we take a tumble.
      Another good reason to learn young that wearing a helmet is important.

      • That year was a much better snow year than this Steve, but Eaglecrest does have some great terrain when the snow comes. I posted that to show the speed that can occur when in the trees, that seems fast but really nothing compared to the speeds on a lot of groomers. Frankly, the idea of hitting a tree even at slower speeds is something that I’m not planning on. However, the best laid plans………

  3. Back in 2011, an acquaintance and fellow climber Renan Ozturk was filming for North Face in Jackson Hole, WY.
    He was skiing with NO helmet on while filming in the mountains.
    “Renan took a fall over a cliff band while filming and skiing with Jeremy Jones, Xavier De La Rue and myself in the sidecountry at Jackson Hole. He hit his head on the way down and suffered a depressed cranial fracture, fractured his c2 and c7 and partially collapsed a lung.”
    After this incident, we all vowed to wear our helmets in the back country and mountain terrain.
    Renan has recovered but still deals with long term deficit from his skull fracture and associated head injury.
    Helmets cost little, injuries and medical expenses can bankrupt your quality of life.
    Why pass on such a good piece of “insurance” as a helmet?
    Does not seem to make sense.

    • I am with ya Steve..for once… Was snowboarding Girdwood several years back and caught a girl out of the corner of my eye who was heading right at me. I went over the front of her skis and while trying to not kill her caught an edge and slammed the back of my head on the super hard icy snow. I never used a helmet and bought a helmet only one week prior. I took a helluva hit and I could only imagine doing that without the helmet.
      Cheap insurance. Some ride motorcycles without helmets and some do. Just stupid without.

  4. NFL vs rugby, one uses helmets the other doesn’t, guess which one has the lower concussion rate…rugby.

    Back when I was a spry young lad I didn’t wear a helmet on the slopes, first time I did I thought I was invincible and it didn’t take long for me to go too hard and too high. I left the slopes that day after crashing harder than I had ever crashed after jumping higher and further than I had ever jumped, turns out a helmet doesn’t make you better. Never wore a helmet on the slopes after that and never jumped anywhere near as high or far, I also never crashed that bad again.

    Wearing a bicycle helmet in a collision with a 2000-3000 pound motor vehicle is not going to help you very much if any, wearing a full suit of body armor probably won’t either.

    • Well Steve O,
      Figuring only 125,000 Americans play Rugby, compared to 5.2 Million Americans playing football…
      You can understand why the latter would produce more concussions.
      BTW my sophomore year in college the dude down the hall from me had a plate put in his head from a Rugby injury that fractured his skull.
      After “Rowdy” got the helo off he was quite the crowd pleaser crushing beer cans on the plate in his head.

      • Hey Steve,
        I think that Steve O is referring to the well documented studies regard professional level football vs professional level rugby in other countries. The level of serious injuries is far higher in the NFL vs rugby – not just brain injuries. People moving at crazy speeds, hitting each other with their full body weight is going to injure more folks than an unprotected athlete moving at a controlled speed and grabbing another athlete instead of trying to dismember their limbs. Not to bag on the NFL – I love football. SKOL Vikings!
        Cheers to all you other folks (who aren’t Vikings fans)!

    • It’s called “losing your nerve” Steve-O. And while helmets certainly don’t make you better, they can make you smarter while skiing.

      • Bill,

        It’s actually called learning a lesson. And your right my experience with helmets made me smarter, it’s why I never wore one on the slopes again.

      • Steve-O, while I’ve never ski jumped I remember talking with a man who did and he said that when the jumper got into the position (similar to shape of an airplane wing) “you could feel the lift it gave you.” At that time jumpers kept their skis together while in the air but today they mostly have them apart at the tips.
        Anyway, that said about ski jumping, the problem for them is clearly the “landing,” rather than that in the air bit. I’m guessing your problems were also with the landing, rather than the “helmet.” Heheh!

      • Bill,

        You’ve missed the point once again. The problem is the false sense of security the helmet provided me, just like it does for countless other people.

      • Call it whatever makes you feel good, Steve-O but only an airhead would think that a helmet would make him a better (skier, jumper, etc.). I’m guessing you were an airhead at the time and doubly so now by choosing not to wear a helmet skiing, even though it appears that you’ve relegated yourself to the 12 mph that those helmets are designed for.
        Your assumption about the countless other skiers is just that-your assumption with nothing backing it IMO.

      • Bill,

        Just to be clear, do you think using a helmet that is designed to protect your head at “the 12 mph that those helmets are designed for” while you are going well over 12 mph is a good idea? Well that explains a lot. You probably are also not aware of the fact that these helmets only provide limited protection for your head and do nothing for the rest of your body.

        Skiing, snowboarding, bicycle riding, rock climbing, football, rugby, and many other things are inherently dangerous activities, just like driving a car is. Do you wear a helmet when you drive your car to the store Bill? Chances are you have much more risk driving in your car to the store than skiing, based solely on the amount of time doing one over the other.

        Point of fact is that helmets can, and do, provide a false sense of security. Re-read the article posted above these comments, loosen the straps on your helmet and try to actually understand it this time.

      • Steve-O, here you are asking me a question and then answering it for me. Have you lost your mind? This is not rocket science but you somehow think it needs to be made out like it is. Helmets are protective for many sports-not the ultimate answer for all but clearly an answer for many. The fact that you are suggesting that a helmet does not protect the rest of the body tells me that you don’t have a clue about this subject and are just wanting a pissing match.
        Well you’ve gotten it and you can just keep up with the bullchit but nobody is buying it. Like I said you can call it what makes you feel good but that doesn’t make it so. You’ve not backed up your comment about helmets do provide a false sense of security (I’ll buy the bit about it “can” give that to some but not the countless numbers you speak of). We’ll give it to you that it gave you this false sense of security because you were an airhead at the time, since this is the honor system.
        What any of this has to do with wearing a helmet while driving a car is pretty telling, too.

      • Bill,

        You are the only one in a pissing match. I told a story about when I was younger, you decided that you wanted to start and argument for some reason. Have fun pissing all over everything Bill, just like you always do.

        Read the article above, it might offer some insight for you as to what my comments have to do with this whole conversation.

      • Steve-O, you were an airhead when you thought your helmet would make you better at your sport (without increasing your expertise) and you are still one by not wearing one today.

      • Bill,

        You think wearing an inadequate helmet protects you, I know an inadequate helmet does not protect me. You probably cannot understand the difference due to the repeated head trauma you have exposed yourself to.

        For some reason you think that I am against using helmets, I’m not. When I use helmets I use the appropriately rated helmet, I’ve never rode a motorcycle or snowmachine without one. The fact that you do not understand the difference between wearing the appropriate protective gear and that you seem to revel in the fact that you wear helmets that you know don’t protect you is astonishing.

        All your childish name calling is making more and more sense. Repeated head trauma has a lasting impact on brain function. I learned my lesson at a young age on the slopes, and I ride within my limits.

  5. Good column, Craig. We should constantly be trying to reduce bike injuries, but I also like to keep in mind the bigger perspective. If more people get injured because more people are biking, then presumably more people are also getting more exercise and therefore are suffering less from other health issues.

  6. We must all care about these types car-cyclist crashes but we must also ask, what if there was a way drivers could start the braking ¾ of a second sooner and stop 30 – 40 feet shorter even at school yard speeds. Perhaps in an even shorter distance than the best driverless cars. There is. Sad that those in charge of driver legislation and training refuse to teach student drivers the safer left foot braking method and ban driving instructors from teaching the very complicated and difficult to mentally maintain especially for older drivers (over 40!), dangerously inefficient (poor stopping distance) and even more dangerous (right foot pedal errors), right foot braking method on automatic transmission and electric cars. See DOT HS 811 597, 812 058 and 812 431(spaces required). These reports showed the flaws of the right foot braking method and that woman drivers seemed to have the most difficulty with it (men as well if they would admit it). But for some unknown reason no more research has been done and the boys don’t want to talk about it. One would have expected that instead of just continuing to blame female drivers they might have asked themselves two basic questions:
    1. Is it possible to develop a braking method that would be more suitable for female drivers (and male drivers if they would admit it), which would prevent these crashes?
    2. Do we actually have any scientific justification for teaching the right foot braking method?
    The answer to point one is YES and the answer to point 2 is NO!
    Turns out there is no scientific justification for teaching the right foot braking method! Deaths to date, 150,000 (19 every day!) pedestrians (in and out of buildings) and cyclists. This is not about which braking method is safer but why they refuse to scientifically compare the two methods. Apparently ME TOO is not the only victim of a male systemic belief! Was it driver error or the way we taught them to brake? ‘That’s the way it’s always been taught’, is not a scientific justification!

  7. Having done a bit of skiing but never in Colorado, I can only assume that (for some reason) Colorado places a few trees in their groomed runs to stop those male skiers after they lose control. What a great idea.

  8. Some of the worst drivers on the road are cyclists. If cyclists are to share a road with licensed drivers in registered and insured autos; then cyclists should be required to at least be registered and carry liability insurance for the damages they cause to others on the road.

    • a.) i don’t personally know a cyclist who ISN’T licensed. b.) do you have any idea how many unlicensed drivers there on the roads of Alaska now? c.) given a + b, why in the world would you want to spend money trying to license cyclists?

      this state doesn’t have enough fiscal problems?

      • Devil’s advocate, Craig: Given the amount of non-motorized and bike only paths in AK (I live in Talkeetna and there’s got to be close to 25 miles of these trails that have been paid by government funds – I can only assume that Anchorage and the rest of the state have many times those miles), is there a reason that bikes aren’t required to purchase registration to help fund that infrastructure? I ride in the summer only, but I’ve always thought that a user tax might be a positive thing – like going to a state or national park and paying for it. As a much more serious rider, what are your thoughts?


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