https://www.nature.com/articles/s41598-022-11559-0

There is more to it then just that simple… for starters, the type of high speed accidents on motorcycles that cause massive trauma leading to instant or delayed death, are not helped by the presence or absence of helmet. Human body is quite frail and at high speed accidents, helmet only serves as a brain bucket… saving some effort for the cleaning crew. The accidents where life-saving differences are made by the use of helmet are relatively low speed accidents, which are far more numerous in number. And this why effect of helmets on donor organ count. High speed accidents can often do, damage internal organs to the degree that they are not useable.

I dislike blanket generalizations not backed up by research. Motorcycle fatalities are not eliminated by helmet use, but they are diminished.
People like to make the perfect the enemy of the good. Why this tendency comes out so prominently during disagreements is not clear to me, but it's a general human failing as far as I can tell.

• Motorcycle helmets are 37 percent (for riders) and 41 percent (for passengers) effective in preventing deaths.6
• Helmets reduce the risk of head injury by 69%.

etc.

https://www.bridgemi.com/michigan-go...ichigan-adults

And yet, you chose to cite the broadest generalization of all, representing information from all motorcycle accidents and fatalities!

My comment was addressing high speed accidents and I specifically stated that the difference in fatalities comes into play in accidents at lower speed.

By the way, quoting CDC hardly qualifies for research; and lately, they have not even been reliably credible. But then everyone has their likes and dislikes, and that’s what makes life interesting. 😉

Sorry, but that's wholly unconvincing. According to your assertion, low speed accidents that cause head trauma are few in number. And yet, there is that 40% reduction in fatalities by helmet-wearing. Are you now going to say, "yes, I meant 40% is a small number."?

And had you bothered to dig a little, you'd have noticed that the info on the cdc site was simply quoting a study from the NHTSA.

https://crashstats.nhtsa.dot.gov/Api...ication/813112

The gathered statistics in the cited NHSTA's Traffic Safety Facts only provides a count of fatalities and percentage victims who were known to have been wearing/not wearing helmets death at time of the fatal event. It in no way provides any confirmation that helmets "prevented" motorcyclists' deaths. It provides no information or clues about how many fatalities, if any, would have been prevented or reduction in significant head injury if unhelmeted victims had worn helmets.

The cited CDC report and its methodology is no better at proving anything about the effect of helmet wear or helmet capability at preventing motorcyclists death at any speed.
The CDC methodology of estimating the lives and costs saved estimates, as well as injury details, is derived from the same set of data cited in the NHTSA document. As Alan K points out the CDC did no "research" on the subject, and its report just made a lot of assumptions about potential benefits from helmet wear that cannot be substantiated from the fatality statistics provided by NHSTA or FARS

Well, Alan, you have I-Like-To.... on your side. Apparently, he rejects the entire premise of epidemiology. Lucky you.

What does epidemiology has to do with motorcycle, is riding it a disease?

Then again, may be someone changed the definitions - I can barely keep up with made-up terms and reinvented sciency gobbledegook.

Rather than claiming what I reject or accept, without knowing it, please read carefully what I stated originally.

Not sure from where did you get that!

Apparently the new version of "epidemiology" allows looking at total numbers of fatalities with and without helmets, and without any data on the percentage of motorcyclists who wear helmets when riding, or the nature and extent of the injuries suffered by the victims of the fatal events can determine the prophylactic power of helmets from the limited data at hand.

The same epidemiologist can use the same analysis method to gaze at the NHSTA data set to determine the prophylactic power of reducing engine size of motorcycles again without knowing anything about percentages of riders who ride bikes with big engines.

More importantly such "analysis" ignores all other variables at play including that riders of big bikes or riders without helmets may ride differently than riders who ride ride small bikes or wear helmets.

My experience, so completely anecdotal: I was wearing a ~$70 Bell (Influx?) 2013 when my rear tire blew while I was going about 25 mph. Apparently I'd been careless and did not tighten the chin strap. The tire came off the rim. I only managed to bleed my speed down slightly when it came off entirely and jammed in the seatstays. Threw my hands off the bars, me over and into a head and shoulder crash. I have a vivid memory of my helmet grinding along the pavement, then all went blank until I came to a stop. (Not a concussion. Just my fully aware brain or body deciding that Ben really didn't need to see the damage happening. As soon as I stopped I was 100% with it. The car I knew was behind me was exactly where it belonged so no loss of time sense.) There was a cyclist behind me who stopped, asked me how I was, then walked with me as I wandered around the park I was passing and assessing the damage to myself. He questioned me for a while; looking for evidence of concussion. I didn't ask but I'm pretty certain he had first aid skills or more. Maybe the angel I really didn't need that day. He offered to call 911 but I had him just call a taxi to take me to the nearby Urgent Care. (Excellent outcome and I saved thousands.)

So, the damage to me. Broken collarbone, ribs. An acre or two of road rash (both sides). Scrape and blood from my glasses being knocked off. The helmet spun a lot and also cut my ear with the strap. But no concussion.

And an aside - I had a TBI 35 years before this when I crashed that famous Lambert fork. Lived only because I was wearing Bell #1. (Well, not #1, but year two of the original Biker.) 5 day coma. And after that, concussions happened easily. I've received concussions from hard body-slam crashes where my head and helmet never hit. To do this last crash, hit that hard and not have a concussion - big, big surprise.

3 weeks later I read about the new MIPS technology being developed in Sweden. Got thinking. That loose strap. Helmet spun 30? degrees, nearly taking my ear off and violently knocking my glasses off. Was that spin why I had no concussion? Something had to be going on for this NFL lineman's abuse brain to come through unscathed.

I was sold on the MIPS technology right then. Bought the first white MIPS helmet I saw, the MTB POC Trabec. 6 years later, the POC closest to that one. New name and a slightly nicer helmet. (Both are built to very high standards and are very comfortable. Yes, MTB weight, not road weight but I don't notice that riding.)

With time, it seems that the MIPS concept works and does often improve outcomes. I don't expect it to save my hide. I didn't expect that original Bell to either but without it, I wouldn't be here. So far, I have not tested either of those POCs. May it stay that way, please.

Epidemiology has its roots in disease, but has been the basis of vehicular safety studies for more than 50 years. If you want any kind of understanding of risk assessment based on objective data, maybe catching up a little wouldn't be a bad idea. Cause otherwise, like The Dude said, then that's just your opinion, man.

And here I was thinking I’m submitting a manuscript for publication in Science, my mistake.

I’m beginning to understand the reason for your poor understanding of scientific principles - if you want to understand science, stop paying attention to Dude!
Dude has no concept of cause and effect - he is easily convinced if someone throws a bunch of numbers at him and make it seem sciency. Example:

Ownership of a Lexus LS460 is statistically significantly associated with lower infant mortality.

You and your Dude must think about cause and effect to grasp the reality.

Thought you all might find this interesting. It's his latest blog, so there will be some scrolling to get to the helmet stuff. I found myself nodding a lot.

I think he overstates when he asserts that EPS is not good at shock absorbing. EPS will absorb more or less well depending on its density. But I'm on board with the general notion that you could make helmets a little safer by making them bigger and thicker - which would make them even harder to sell.

My general take on helmets is that they provide useful protection for bike crashes. In particular, they reduce your chances of injury from hitting your head on the ground from a fall. The cost is low. the inconvenience is low. So why not?

A helmet probably kept me out of a hospital and maybe even out of a grave when I went over the handlebars of my bike. Hard to say for sure what the outcome would have otherwise been. But the helmet damage suggests a hospital visit as a minimum. But I don't see how a helmet is likely to help much with the forces involved when a car hits a cyclist. As the blogger points out, they are designed with a 14mph or less collision in mind. So if a car merely knocks you down, then its more likely to help. But if it hits you with substantial force, The helmet will provide little protection.

So I think its generally a good idea to wear a helmet. Even when you aren't riding around cars. But I think the strong and even zealous advocacy I often see oversells the potential benefit. If people looked at actual risks they might be just as concerned about head injuries with other daily activities - like walking (especially after age 65) and driving.

[MENTION=573049]Jay Turberville[/MENTION], I think Grant's main objection was to using rigid styrofoam instead of something squishier that slows your brain down before stopping it. And I agree, there's not much a foam hat can do against a Ram 1500.

Other than the kapok-stuffed leather hairnets that we racers used in the '60's and '70's, all bike helmets (e.g., the popular Pro-Tec helmets) used "squishier" foam before Bell came out with their expanded-polystyrene-lined helmets. Once the ANSI (and Snell) began testing bike helmets, the helmets with spongy foam (to say nothing of the hairnets) all but disappeared from the market, since they could not meet the relevant safety standards.

Styrofoam hats, on the other hand, earn approval from the testing agencies because the EPS crushes on impact, thus absorbing energy and lessening the likelihood or severity of concussion.

(By the way: no, an EPS-lined helmet won't protect you from a hit from a speeding car. To argue, as some posters here are prone to do, that such a helmet is therefore useless for a bike rider is like arguing that steel and Kevlar helmets are useless for ground troops because they won't protect against a direct hit from a mortar shell.)

Instead of bloviating about bike helmets from his position of highly opinionated ignorance, Petersen should interview an engineer or two from Bell or Giro or one of the other current helmet manufacturers and learn a little about the subject.

Agreed. I haven't read the entire thread or even all of the last page or the recently linked article. But I've never worn a helmet expecting much protection from a vehicle at speed. While getting hit from a car or truck is certainly in the realm of possibility, it fortunately has not happened. What has happened is getting ran off the path by an inattentive rider, or an e-bike going too fast. I've crashed due to wet roads, loose gravel or mud and while I did not have a head impact if I had I would have been glad to have had the helmet. I've had close calls from people backing out of driveways, right hooks or pulling out in front of me at intersections.

It makes no sense to not wear a helmet because it can't protect against things beyond its design limits.

I understand his point. I just disagree with much of it. Something squishier and of a similar thickness won't slow the head/brain (absorb very much energy) much before it stops it. He also thinks using eggs is a proper test - somehow missing the major point that the mass of an egg is so much less than that of a human head. Whether an egg shell cracks or not isn't a particularly good model for evaluating head protection. Nor is pressing your thumb against some Styrofoam. His arguments against EPS are weak. He seems to misunderstand the issues around absorbing energy which is the key role that EPS plays.

The design problem for bicycle helmets is hard. How do you add useful protection in a lightweight design? Well, the fact is that you can't do it very well. There are some basic physics issues involved that are very hard if not impossible to get around. Automobiles manage the forces by having large crush zones and spreading impacts over larger areas of the body. (They also use EPS in their bumpers and other places for energy absorption). A large crush zone on a helmet would be unwieldy. Who would use it? And it is no wonder that football helmets don't use EPS. The helmet needs to withstand repeated impacts. EPS is useful one time. But motorcycle helmets use EPS as the primary material for impact energy absorption. He's simply wrong to assert otherwise. He also seems to think that rock climbing helmets don't use EPS, but they often do. Likewise, EPS is commonly used in horse riding helmets. I could go on.

https://www.trekbikes.com/us/en_US/e...elmets/c/E399/

Please explain what the point was of posting that link.

Non-stryofoam helmet. Just adding to the conversation.

My $50 Specialized Align II received better performance test results in the Virginia Tech Ratings. Bontrager's own Rally MiPs helmet outperformed all of their WaveCell helmets. Also, some WaveCel helmets also have portions lined with EPS. It is great that people are trying to improve cycling technology. MiPs is one such attempt. And WaveCel may have some advantages that the Virgina Tech testing doesn't reveal. So the marketing video from Bontrager seems to me to be utter BS likening an EPS helmet to 30 year old steel bike frame technology and their new WaveCel technology to a modern carbon fiber bike - that is "better in every way." But unlike the modern bike, the advantages are not clear at all. They appear to be marginal to non-existent if Virginia Tech's helmet testing protocol is to be believed.

Mr. Petersen has made a cycle industry career out of 'everybody else is wrong and I'm right'. He's built a small following over the last 30+ years.