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Bicycle Helmet Ratings (vt.edu)
36 points by luu 50 days ago | hide | past | web | favorite | 14 comments

> A lower score offers better protection.

I don't understand why anyone would present the data like this, sure, 'lower is better' makes sense in benchmarks where you're presenting a raw timing or such, but with an arbitary unit like 'score' just invert the data so bigger -> better and let people's human nature take over.

I think it depends no how this score is determined. If their rating methodology allows them to determine an upper bound on protection better than a lower bound, then it's better to set that bound to score zero, to not risk later needing scores with negative numbers.

The formula seems to be on the following pdf on the third page.


That's a funny query parameter, by the way. I tried setting isAllowed to n, but it still gave me the pdf, so who knows what it's for.

> I don't understand why anyone would present the data like this, sure, 'lower is better' makes sense in benchmarks where you're presenting a raw timing or such, but with an arbitary unit like 'score' just invert the data so bigger -> better and let people's human nature take over.

Also for bicycle helmets it makes sense, i.e. force to the head -> lower is better.

Especially when more stars is better! Overall their testing methodology looks good, so it's a little disappointing that the presentation is so counterintuitive.

Their primary presentation is the 0-5 star rating which is perfectly intuitive.

If I'm reading the methodology correctly, the actual STAR score represents the incidence of concussion, in which lower is certainly better.

The only real confusing thing I see is the "star" naming of the "STAR evaluation score" vs. using a "star rating" (0-5) and how they are actually separate things.

I agree that the stars are clear, I wonder if there's any point in displaying the score at all, given that.

Note for those looking for this helmet, from [1]:

“Footnote, May 30 2019:We have since received word that the Cyclone MIPS is an older model that has been discontinued by Lazer – and suspect, given the likely spike in interest as a result of the Virginia Tech update, that the brand may be regretting that decision.”

This is particularly unfortunate, since the scores for two Lazer MIPS helmets vary quite widely on the test in question, so it's not clear you could just go with another model.

[1] https://cyclingtips.com/2019/05/wavecel-vs-mips-virginia-tec...

I think the key take-aways are:

* any helmet provides significant protection vs. not wearing a helmet

* there is no correlation between cost and protection level

* there may be a correlation between protection and rotational-focused technologies (i.e. MIPS et al) but it's hard to tell because most manufacturers don't have a non-MIPS product anymore (where they do I don't see both the MIPS and non-MIPS models here)

I have a Giro Synthe MIPS, and I would avoid them: they designed the sweatband wrong, so that it all drains right down into your eyes.

It bugged me so much I got a Bell helmet that has a little tab that takes the sweat out away from your face so it can drip down unimpeded. It looks kind of gimmicky, but it works pretty well.

Have you tried a Halo band? Sounds somewhat similar... it's a neoprene headband with a rubber squeege-like trough on the inside. It channels the sweat back behind your ears and down your neck.

They are awesome and when I ride without one I always regret it. Well worth the 15-ish bucks and vastly superior to extra padding or a bandana.

They make a visor and hat for runners but not as impactful as the headband. Highly recommend!

Helmet technology made an important leap in the last few years by adding protection against rotational forces. If you are in the market for a helmet, consider getting the MIPS version (or Bontrager's Wavecell). MIPS costs only slightly more than the same helmet without it.

Having been in oddly many very different bicycle accidents of varying levels of catastrophe, I have a hard time believing that rotational forces are a real problem and not something made up by marketers trying to sell a new widget. Helmets are approximately half-spheres which bounce and skid. Protruding elements like visors are made to break away with minimal force so that nothing can catch. The contact surface is small and the external shell is hard and slick. So where is the rotational force coming from?

If you watch the video at https://mipsprotection.com their test scenario is the most bonkers forced thing I've ever seen. Their idea of a collision is where you are completely upside down with your feet are straight up in the air and your head straight down and you're falling onto a 45 degree incline. Screenshot: https://imgur.com/kIFN1ds

And besides all of that, the MIPS people talk about "10-15mm relative motion". It's hard to imagine that any random bike helmet strapped to any random head doesn't already give 10-15mm of relative motion even without MIPS.

This seems like a cool & intuitive technology, but I'd caution that (similar to the popularity of neck braces) it's far from definitive to provide additional protection.

The general principle is MIPS (and others) allow the helmet to receive a rotational force without "grabbing" your head and twisting it as well, but unless you have a shaved head I find this is exactly what happens with the original MIPS, hair.

So I'd say: (1) the science is still undecided in my opinion, (2) I wouldn't replace a new helmet just to get MIPS, (3)your next helmet is likely to have it because they all do.

The 'score' value is a bit counterintuitive and offers no further explanation past:

> A lower score offers better protection.

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