Go Back  Bike Forums > Bike Forums > Advocacy & Safety
Reload this Page >

The helmet thread

Notices
Advocacy & Safety Cyclists should expect and demand safe accommodation on every public road, just as do all other users. Discuss your bicycle advocacy and safety concerns here.
View Poll Results: Helmet wearing habits?
I've never worn a bike helmet
178
10.66%
I used to wear a helmet, but have stopped
94
5.63%
I've always worn a helmet
648
38.80%
I didn't wear a helmet, but now do
408
24.43%
I sometimes wear a helmet depending on the conditions
342
20.48%
Voters: 1670. You may not vote on this poll

The helmet thread

Old 08-13-14, 02:39 AM
  #8401  
Senior Member
 
CarinusMalmari's Avatar
 
Join Date: May 2014
Location: Netherlands
Posts: 223
Liked 226 Times in 131 Posts
Originally Posted by Mvcrash
I don't think bike helmets should be mandatory. I don't think they are the end of all head injuries.
Let's see what the people who make them have to say about them:

Originally Posted by Bell
Limited Impact Protection
Helmets cannot always protect against injury. Even a very low speed
accident can result in serious injury or death. Any helmet subjected to a
severe impact should be discarded and destroyed, even though damage
may not be outwardly visible. Since this helmet is made of polystyrene
foam, there is a chance it may be penetrated by sharp objects.

HELMETS CAN’T PREVENT ALL HEAD INJURIES
Some head injuries are not caused by impacts at all, but by other forces.
You can scramble an egg just by shaking it. You don’t have to break the
shell to destroy the contents. Helmets cannot prevent this type of injury.

Helmets Can’t Protect What They Don’t Cover
This helmet will not protect the neck or any areas of the head that it does
not cover. It cannot guard against spinal or other bodily injuries that may
result from an accident.
tl;dr "Maybe it works, maybe it won't, but I wouldn't count too much on it"
Not very impressive for a piece of safety equipment that costs up to 300 dollars.
https://www.bellhelmets.com/en_eu/product-manuals/

I think that they give you a better chance of avoiding a serious brain injury.
There's really no evidence for that. All we really got is a bunch of helmet fan boys and girls who think that some busted Styrofoam is solid proof that someone was saved from grave injuries and/or (a fate worse than) death.

If you think they don't help at all, don't wear one. My thought is that if they save one person from one brain injury.....why not.
This is such a classic "argument". I reckon you promote wearing a bicycle helmet all the time? Because people get hurt/die all the time while slipping in the shower/tripping on the stairs/falling out bed/etc.etc.etc and if they save one person from one brain injury.....why not.

Who would have known postmortem examinations yield such an abundance of helmeteer platitudes...

Last edited by CarinusMalmari; 08-13-14 at 02:47 AM.
CarinusMalmari is offline  
Old 08-13-14, 04:16 AM
  #8402  
Senior Member
 
rekmeyata's Avatar
 
Join Date: Sep 2010
Location: NE Indiana
Posts: 8,697

Bikes: 2020 Masi Giramondo 700c; 2013 Lynskey Peloton; 1992 Giant Rincon; 1989 Dawes needs parts; 1985 Trek 660; 1985 Fuji Club; 1984 Schwinn Voyager; 1984 Miyata 612; 1977 Raleigh Competition GS

Liked 260 Times in 209 Posts
^^My God the ignorance with the above post is just overwhelming. OF course a helmet has limitations beyond what they're design to do, NO ONE IS QUESTIONING THAT! Everything made for the cause of safety has limitations beyond what their designed to do, your seat belt will not guarantee that you'll live or not be injured in a car accident, your airbag cannot make that guarantee either. Really? you have to make such an ignorant post like that? If that's true that you have to make a statement like that then you just made a case for not wearing seat belts and having the air bags activated because they can't guarantee that either, and the companies that make these devices make those statements to that effect because THEY DON'T WANT TO BE SUED FOR MAKING FALSE STATEMENTS BASED ON A LIE!!! The same is true with bicycle helmets.

This makes your point absolutely POINTLESS.
rekmeyata is offline  
Old 08-13-14, 04:40 AM
  #8403  
Senior Member
 
CarinusMalmari's Avatar
 
Join Date: May 2014
Location: Netherlands
Posts: 223
Liked 226 Times in 131 Posts
Originally Posted by rekmeyata
THEY DON'T WANT TO BE SUED FOR MAKING FALSE STATEMENTS BASED ON A LIE!!!
What do you know, if you sift through all the mindless and incoherent drivel that you produce, sometimes you find a rare gem of insight in the matter at hand. It's probably one of those "a-million-monkeys-beating-a-million-keyboards-for-eternity" things, but still.

And FYI a lot of manufacturers of safety devices do make bold statements about their product, and guarantee their product will function to a certain extent. And yes, you can sue them when their product doesn't live up to that standard. Bicycle helmets manufactures don't, and instead let useful idiots do the advertising for them. It's a brilliant way to sell cheap Styrofoam gadgets for outrageous prices without any risk of lawsuits, really.

Last edited by CarinusMalmari; 08-13-14 at 06:40 AM.
CarinusMalmari is offline  
Old 08-13-14, 06:45 AM
  #8404  
Senior Member
 
Join Date: Dec 2013
Location: antipodes
Posts: 142
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by CarinusMalmari
Well, we where talking helmets, really, and i think it's fairly obvious what the differences are. Compared to motor helmets, bicycle helmets are flimsy contraptions than made concessions to improved weight, ventilation and comfort over protection, to the point where bicycle helmets lost most of their protective value.
Not to mention that, at least where I live, motorcycle helmets are penetration tested but bicycle helmets are not. This makes a big difference in effectiveness, but also weight and ventilation. Australia's mandatory helmet laws would not have been implemented if the pen-test standard was not removed - meaning that to make helmet laws palatable to cyclists they made helmets less safe. Logical isn't it?
yugyug is offline  
Old 08-13-14, 06:51 AM
  #8405  
Senior Member
 
Join Date: Dec 2013
Location: antipodes
Posts: 142
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by rekmeyata
^^My God the ignorance with the above post is just overwhelming. OF course a helmet has limitations beyond what they're design to do, NO ONE IS QUESTIONING THAT! Everything made for the cause of safety has limitations beyond what their designed to do, your seat belt will not guarantee that you'll live or not be injured in a car accident, your airbag cannot make that guarantee either.
The issue is that the design limitations of helmets make their effectiveness rather low, much lower than seat belts and other safety equipment. Yet the perception of helmets benefits from the experience we have with other safety equipment which have higher levels of efficacy. Helmets are not placebo, but for many cyclists they are kinda close.

EDIT: is it effectiveness or efficacy? Which I did I just use correctly? Anyone care to illuminate me?
yugyug is offline  
Old 08-13-14, 06:56 AM
  #8406  
Senior Member
 
Join Date: Dec 2013
Location: antipodes
Posts: 142
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Brennan
Confronted by another helmet nanny today. Riding along with my wife, both of us un-helmeted, my wife waves at a cyclist going the other direction. The guy returns the greeting with a smug look while pointing to his helmet. So obnoxious.
Thats hysterical. What a c--t. Just for fun I might start doing the same thing, point to my bare head and give a smug look when I ride past cyclists who are wearing helmets. This will be very confusing for them because where I live not wearing a helmet is actually a crime.
yugyug is offline  
Old 08-13-14, 07:36 AM
  #8407  
Senior Member
 
CarinusMalmari's Avatar
 
Join Date: May 2014
Location: Netherlands
Posts: 223
Liked 226 Times in 131 Posts
Originally Posted by yugyug
meaning that to make helmet laws palatable to cyclists they made helmets less safe. Logical isn't it?
Bicycle helmet advocate logic works in mysterious ways.
CarinusMalmari is offline  
Old 08-13-14, 07:48 AM
  #8408  
Cycle Dallas
 
MMACH 5's Avatar
 
Join Date: Jun 2005
Location: Land of Gar, TX
Posts: 3,777

Bikes: Dulcinea--2017 Kona Rove & a few others

Likes: 0
Liked 10 Times in 5 Posts
Originally Posted by yugyug
Not to mention that, at least where I live, motorcycle helmets are penetration tested but bicycle helmets are not. This makes a big difference in effectiveness, but also weight and ventilation. Australia's mandatory helmet laws would not have been implemented if the pen-test standard was not removed - meaning that to make helmet laws palatable to cyclists they made helmets less safe. Logical isn't it?
In the rare event that a cyclist accident involves a head strike, does the helmet really need to be puncture-proof? Consider the speed of a motorcycle vs the speed of a bicycle. How often is a cyclist going to hit anything fast enough to need that type of protection?
MMACH 5 is offline  
Old 08-13-14, 08:49 AM
  #8409  
Banned
 
Join Date: Apr 2010
Location: Lincoln Ne
Posts: 9,924

Bikes: RANS Stratus TerraTrike Tour II

Liked 1,057 Times in 636 Posts
carinus

When you go down sometime, and you will, if you want to use your bare head for a brake pad, go ahead it is your option to do so.
rydabent is offline  
Old 08-13-14, 09:11 AM
  #8410  
Senior Member
 
Brennan's Avatar
 
Join Date: Mar 2003
Location: Midwest USA
Posts: 697

Bikes: Surly X√, Trek Earl

Liked 12 Times in 7 Posts
Originally Posted by shipwreck
I've never been really influenced or impressed by either sides arguments on the helmet subject. However, I would have to say that the tendency of the pro helmet safety shamers to do things like that tips the scales to the side of the non helmet your a fool to believe the helmet myth crowd who don't tend to do things like that. As someone who REALLY dislikes people telling me what to do, that's a win for your side.
That's really all I am looking to get out of this, to be left alone. People can argue the merits or fallacies of bicycle helmets all day long, but I'm not too invested in that debate. I have studied the issue myself and made my decision. All I ask is that people respect my right as a 40+ adult, with as many years riding a bike under my belt, to make my own decisions regarding my personal safety. Unfortunately, these unwelcome confrontations with strangers are all too common. By my count, this is about the seventh time it has happened. A couple of them have actually yelled at me. Do they really think this approach will convince anybody of anything? It's really disagreeable all the way around.

Last edited by Brennan; 08-13-14 at 11:46 AM. Reason: spelling
Brennan is offline  
Old 08-13-14, 09:49 AM
  #8411  
Senior Member
 
mconlonx's Avatar
 
Join Date: Jun 2007
Posts: 7,558
Liked 134 Times in 92 Posts
Originally Posted by Mvcrash
Actually, they are designed to do the exact same thing as a motorcycle helmet, just not at the same speeds. Helmets simply extend the distance, and as a result, the time it takes your head to slow down from whatever speed you were moving, to Zero. Hitting the pavement, instant stop. Wearing a helmet adds time and distance to make the slowing down take longer as the helmet absorbs some of the energy.
Football helmets do the exact same thing. Energy absorbtion over time and distance. When football players contact each other, it is just another crash (slowing down). I'm not sure how they are going to fix it.
They work on the same principals, but design and manufacture are intrinsically different. So are safety standards/testing. And someone posted a study here in this thread previously which indicated that football helmets do not appreciably help mitigate concussion injury... not that it has anything to do with bicycle helmets.
mconlonx is offline  
Old 08-13-14, 09:51 AM
  #8412  
Senior Member
 
mconlonx's Avatar
 
Join Date: Jun 2007
Posts: 7,558
Liked 134 Times in 92 Posts
Originally Posted by Mvcrash
But safer on both with one.
I would argue that you are safer on a horse with a helmet than on a bike with one. Bikes don't try to kick you in the head or bite you.
mconlonx is offline  
Old 08-13-14, 09:55 AM
  #8413  
Senior Member
 
mconlonx's Avatar
 
Join Date: Jun 2007
Posts: 7,558
Liked 134 Times in 92 Posts
Originally Posted by shipwreck
Now watch tomorrow on my fast ride that I wear a helmet on, as I get cornered by someone who wants to tell me all about rotational injuries and how wearing some Dumbo's feather on your head makes cycling look dangerous to the general public.
Thing is, and the valid point the barehead brigade brings up, is that this never happens. While you directly experienced the flipside, helmet users evangelizing and proselytizing to bearheaders.
mconlonx is offline  
Old 08-13-14, 10:27 AM
  #8414  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by rekmeyata
^^My God the ignorance with the above post is just overwhelming. OF course a helmet has limitations beyond what they're design to do, NO ONE IS QUESTIONING THAT! Everything made for the cause of safety has limitations beyond what their designed to do, your seat belt will not guarantee that you'll live or not be injured in a car accident, your airbag cannot make that guarantee either.
This would have been a very intelligent reply if you had actually understood what the limits for a cycling helmet are - which the post you were responding to seems to have assumed, unfortunately over-estimating you. In summary:

- Helmets are designed to take only the impact of your falling off the bike. That's it. And they'll only take said impact if you fall so that the helmet takes the weight of the head only. That's around 150 joules of energy

- Virtually all cyclist deaths, however, come from heads or torsos being hit by ton plus cars moving at +30mph. That's about 80,000 joules. So about FIVE HUNDRED FREAKING TIMES OVER THE HELMET SPEC.

...This was the point that was being made. And what you are doing in a debate like this if you don't know basic facts, like the amount of energy a helmet can take and the amount in a typical fatal crash, is beyond me.

Last edited by meanwhile; 08-13-14 at 10:40 AM.
meanwhile is offline  
Old 08-13-14, 10:40 AM
  #8415  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Mvcrash
The cracking of the plastic takes energy. Energy that does NOT get transferred to your head.
A helmet that does not crack absorbs around 150J - most of this is from liner compression. So for a cracked helmet - where a liner won't compress properly - pencil in about 20J of energy lost. Compared to about 80,0000J for a typical fatal accident.Do you think that subtracting 150J from 80,000J makes any difference to your chances of survival?

If you're going to make physics based arguments, USE NUMBERS. Otherwise you're like a crank saying "I have to stand a better chance of surviving this a-bomb at Ground Zero if I wear sun screen!" (Btw - have any engineers of scientists at all posted on the pro-helmet side? My memory is that every single qualified person read the helmet spec and went "Mygawd - this is useless!")

Last edited by meanwhile; 08-13-14 at 10:52 AM.
meanwhile is offline  
Old 08-13-14, 10:41 AM
  #8416  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 39,308

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Liked 3,153 Times in 1,741 Posts
Originally Posted by rydabent
carinus

When you go down sometime, and you will, if you want to use your bare head for a brake pad, go ahead it is your option to do so.
Yes, people do fall or crash on bicycles. But the evidence of over a century of people doing so is that head injuries only occur in a small percentage of these crashes. Of those small number, only a percentage are of a type and energy level where the helmet would make a critical difference. The rest are either light impacts where no injury would occur, or at energy levels where head injury or death are inevitable, helmet or no.

There's no denying that helmets can make a critical difference in those accidents that fall within their band of effectiveness, but those are a small percentage of a low percentage event.

So if you claim to be a cold logician, stop spouting the myth that a crash leading to head injury is a likely event, because it isn't.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline  
Old 08-13-14, 10:47 AM
  #8417  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by yugyug
Not to mention that, at least where I live, motorcycle helmets are penetration tested but bicycle helmets are not. This makes a big difference in effectiveness, but also weight and ventilation. Australia's mandatory helmet laws would not have been implemented if the pen-test standard was not removed - meaning that to make helmet laws palatable to cyclists they made helmets less safe. Logical isn't it?
You simply can't have a pen safe cycling helmet and shouldn't try. If you want to have a safer helmet then

1. You need one that forces the wearer to wear it correctly. Most people don't

2. You need a shell that won't shred on a rough surface

3. You need anti-rotation features

...Such a helmet would reduce minor head injuries. It wouldn't substantially impact deaths, because they all result from cyclists heads and torsos going across car hoods and bumpers at +30mph, and no imaginable helmet can manage those energy levels.
meanwhile is offline  
Old 08-13-14, 10:51 AM
  #8418  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by rydabent

carinus

When you go down sometime, and you will, if you want to use your bare head for a brake pad, go ahead it is your option to do so.


Yes: it is realistic to expect a piece of foam to reduce the chances of a grazed scalp. If a low energy crash and a grazed scalp are your concerns, then wearing a helmet makes some sense. (Possibly - because you may be trading scalp tearing for skull rotation, which means a greater chance of brain injury.)

BUT do not extrapolate from this that a helmet will reduce your chances of dying; the types of crash are complete different.
meanwhile is offline  
Old 08-13-14, 10:53 AM
  #8419  
Been Around Awhile
 
I-Like-To-Bike's Avatar
 
Join Date: Oct 2004
Location: Burlington Iowa
Posts: 30,065

Bikes: Vaterland and Ragazzi

Liked 1,609 Times in 1,087 Posts
Originally Posted by FBinNY
Yes, people do fall or crash on bicycles. But the evidence of over a century of people doing so is that head injuries only occur in a small percentage of these crashes. Of those small number, only a percentage are of a type and energy level where the helmet would make a critical difference. The rest are either light impacts where no injury would occur, or at energy levels where head injury or death are inevitable, helmet or no.

There's no denying that helmets can make a critical difference in those accidents that fall within their band of effectiveness, but those are a small percentage of a low percentage event.

So if you claim to be a cold logician, stop spouting the myth that a crash leading to head injury is a likely event, because it isn't.
Good summary but I suggest you define "critical difference" in this context. Given its limited "band of effectiveness" in reduction of impact effects, helmets are seldom likely to significantly reduce serious or worse consequences/injuries of an accident.
I-Like-To-Bike is offline  
Old 08-13-14, 10:54 AM
  #8420  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by yugyug
EDIT: is it effectiveness or efficacy? Which I did I just use correctly? Anyone care to illuminate me?
In this context they're synonyms.
meanwhile is offline  
Old 08-13-14, 11:01 AM
  #8421  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
Cycle helmets are useless, says brain surgeon - Telegraph

A leading neurosurgeon has controversially claimed that cyclists who wear helmets are wasting their time.

Henry Marsh, who works at St George’s Hospital in Tooting, London, said that many of his patients who have been involved in bike accidents have been wearing helmets that were ‘too flimsy’ to be beneficial.



He made the comments while speaking at the Hay Festival during a discussion with Ian McEwan, whose 2005 novel Saturday featured a neurosurgeon.


He cited evidence from the University of Bath that suggests that wearing a helmet may even put cyclists at greater risk. The research showed that drivers get around 3 inches closer to cyclists who wear helmets because they perceive them as safer.



He said: “I ride a bike and I never wear a helmet. In the countries where bike helmets are compulsory there has been no reduction in bike injuries whatsoever.



The article also reference the latest DTI helmet study (which I've lost my link to)

A Department of Transport study has shown that helmets could prevent 10-16 per cent of cyclist fatalities, although this was also an estimate based on a small study.

In fact this study was excellent - it looked at the type of crash and the impact energy and whether a helmet could have absorbed that much energy if it worked up to spec in the real world (there is a lot of evidence that most don't.) So this is the bottom line: if you wear a helmet to reduce the chances of your dying in a cycling accident, then the biggest reduction you can hope for is about 15%. Given that cycling is already as safe per mile as walking, and that training - which most helmet advocates don't have - can reduce your chances of dying by about 50%, this is very small beans.

..And that's before you consider that there is evidence that wearing a helmet will increase your chances of being in an accident. These only have to go up a tiny amount for wearing a helmet to be a loss, because the maximum possible benefit is so pathetically small.
meanwhile is offline  
Old 08-13-14, 11:36 AM
  #8422  
Senior Member
 
Join Date: Aug 2013
Location: Northern NJ
Posts: 456

Bikes: Trek 4900, Cannondale Cx-4

Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by mconlonx
They work on the same principals, but design and manufacture are intrinsically different. So are safety standards/testing. And someone posted a study here in this thread previously which indicated that football helmets do not appreciably help mitigate concussion injury... not that it has anything to do with bicycle helmets.
I agree about the MC helmets. Funny, you can go to a MC website and read the argurments about full face vs. 3/4 helmets vs. skull caps. I also have read studies that indicate bike helmets also have the same issue with the mitigation of concussion injury.

I've never heard a Forensic Pathologist (medical examiner) say..."If the guy did not have a helmet, he would have survived." I have heard "to bad no helmet, he could have survived." Not he WOULD have...just that he could have.
Mvcrash is offline  
Old 08-13-14, 11:40 AM
  #8423  
Senior Member
 
Join Date: Aug 2013
Location: Northern NJ
Posts: 456

Bikes: Trek 4900, Cannondale Cx-4

Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by FBinNY
Yes, people do fall or crash on bicycles. But the evidence of over a century of people doing so is that head injuries only occur in a small percentage of these crashes. Of those small number, only a percentage are of a type and energy level where the helmet would make a critical difference. The rest are either light impacts where no injury would occur, or at energy levels where head injury or death are inevitable, helmet or no.

There's no denying that helmets can make a critical difference in those accidents that fall within their band of effectiveness, but those are a small percentage of a low percentage event.

So if you claim to be a cold logician, stop spouting the myth that a crash leading to head injury is a likely event, because it isn't.
Fatality Facts
Mvcrash is offline  
Old 08-13-14, 12:01 PM
  #8424  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Mvcrash
Junk link. It quotes the discredited "85% study" paid for by helmet makers as it sole source of evidence - this study was officially "shamed" in the last couple when the US government removed it from policy considerations because it was completely worthless. (Bizarrely, the authors looked at two groups of children, one cycling with helmets in parks and the other without on inner city roads, found a difference in minor head injuries, and deduced the 85% figure from this...)

You might want to pay more attention to

“Two things are infinite: the universe and human stupidity; and I'm not sure about the former."
― Albert Einstein


..and start checking your sources in future.
meanwhile is offline  
Old 08-13-14, 12:05 PM
  #8425  
Senior Member
 
meanwhile's Avatar
 
Join Date: Jun 2008
Posts: 4,033
Likes: 0
Liked 0 Times in 0 Posts
There's a discussion of why the 85% study was junk here:

https://www.cyclehelmets.org/1131.html

- this is a site run by professional helmet engineers and statisticians. Oh - and that study is now used as a textbook example of how to do bad/prejudiced science, btw. You can see whyData for children under 15 (the most significant comparison in the Seattle study) are used to illustrate the problem. In Seattle in 1987, observational surveys counted 4501 child cyclists; 3.2% wore helmets (DiGuiseppi, Rivara, Koepsell and Polissar, 1989). Hospital data showed 143 children (the 'cases') had emergency room (ER) treatment for head injury (HI) and 202 had ER treatment for other injuries (the ER controls). 2.1% of HI children and 5.9% of ER controls were wearing helmets.

Nothing can be concluded from the above data. So few children wore helmets that the differences in helmet wearing (HW) for HI and ER controls are no more than expected from random variation; neither is significantly different to HW in the observational surveys. Put simply, about 3% of child riders in Seattle wore helmets, as did roughly 3% of HI children, so from children's hospital data we cannot conclude that helmets offer any protection at all.

However, the Seattle study also considered a second group of cyclists, members of a Group Health Cooperative (GHC) who had fallen off their bikes. 86% of these cyclists were children under 15, so comparisons between this and the other groups are dominated by data for children. GHC children were from households with higher average income and educational levels and 21.1% were wearing helmets when they fell off their bikes.

If we assume the GHC group is typical of children who had bike accidents in Seattle, it would appear that helmets are of benefit. If 21.1% of children in bike accidents wore helmets, but only 2.1% of those with HI, helmets must have prevented HI in the remaining (21.1% - 2.1%) = 19% of children, i.e. helmets prevent 19/21.1 = 90% of head injuries.
This assumption (from the Seattle study) leads to other conclusions. If 21.1% of children in bike accidents wore helmets, but only 3.2% of child cyclists riding round Seattle (DiGuiseppi, Rivara, Koepsell and Polissar, 1989), helmet wearers must be (21.1/3.2) = 6.6 times more likely to have accidents. Thus wearers may be protected if they have accidents, but because they are nearly 7 times as likely to have accidents, their overall risk of HI is similar to non-wearers, but their risk of non-head injury is much higher!
This is bad news for helmet wearers because 57% of HI in the Seattle study were wounds to the scalp, forehead or ears, presumably no more serious than wounds to other parts of the body. Who would want to have 7 times as many accidents in exchange for protection from these often minor injuries?

In fact, you can't conclude anything - the study was junk and just compared two groups with different behavior. The researchers, sponsored by a helmet company, then claimed any positive difference was due to helmets, ignored any negative difference, and pretended any reduction grazes from falling on grass would be reflected in miraculous survivals when hit by trucks.

Obviously, this is idiotic and led to a storm of protests by scientists. But as marketing it was genius - because the marketeers knew that most people are too stupid and lazy to ever check facts and would never hear the study has been completely discredited.

Last edited by meanwhile; 08-13-14 at 12:11 PM.
meanwhile is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Your Privacy Choices -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.