Bicyclist Fatalities in AZ 2009

On Nov 22, 4:22 am, "Duane Hebert" wrote:
"RobertH" wrote in message

...



On Nov 21, 10:14 pm, Frank Krygowski wrote:

If you've got data comparing hospital admissions for cyclists,
pedestrians, motorists and motorcyclists, I'd like to see it. I
suspect it's not going to make cycling look unusually dangerous. One
paper cites Australian data before their mandatory helmet laws, and
shows that hospital admissions for head injury per million hours
activity were not greatly different for cyclists, pedestrians and
motorists. And I don't recall seeing any data regarding hospital
admissions per hour for all injuries.

Total transfers/hospital admissions 2009 (WISQARS):

pedalcyclists ~ 30,000
motor vehicle occupants ~ 178,000
pedestrians ~ 30,000
motorcyclists ~ 47,000

Bicyclists represent about 10% of serious injuries in the group you
mentioned.

By any reasonable estimation bicyclists must have the worst per-hour
rate of serious injury.

That's why they came up with the "per miles traveled" criteria.

The part that I don't get, is comparing pedestrian injuries by
number to cycling injuries by number. What is the percentage
of people cycling? What is the percentage of people walking?

Not to mention, as I've stated before (index that :-): The group of
people that "cycle" are almost entirely possessed of some degree of
good balance and so forth, whereas the pedestrian group includes
everybody that doesn't.

On Nov 21, 9:14 pm, Frank Krygowski wrote:
On Nov 21, 1:24 pm, "Duane Hebert" wrote:

snip


some
cyclists will rush to say "No, that's not right; cycling really is
dangerous!"

Well, there is danger, and you know it. But nobody here is saying it
has to be *terribly* dangerous.


That's what you just attempted to do.

Where? I must have missed it. Point it out for me, okay?

On Nov 22, 2:57*am, RobertH wrote:
On Nov 21, 10:14 pm, Frank Krygowski wrote:

... I don't recall seeing any data regarding hospital
admissions per hour for all injuries.

Total transfers/hospital admissions 2009 (WISQARS):

pedalcyclists * ~ 30,000
motor vehicle occupants * ~ 178,000
pedestrians * ~ 30,000
motorcyclists * ~ 47,000

Thanks. I don't understand the business about "transfers" (to where?)
but querying on just "hospitalizations" gives roughly similar numbers
in about the same proportions.

But we're running into some oddities in data here. That data
(apparently, national estimates computed from a small sampling of
hospitals) claims hospital admissions of cyclists are about equal to
hospital admissions of pedestrians.

Yet we know that ped fatalities greatly exceed cyclist fatalities.
There are roughly 5000 pedestrians, but only 700 cyclists killed per
year. (either from WISQARS or from NHTSA, via a different
mechanism.) How is it that cycling causes as many hospitalizations as
walking down the street, yet walkers get killed six or seven times as
often? The fatality counts for cyclists and peds aren't even close.
Walking causes far more deaths.

Also, on fatalities: WISQARS says there are about 5300 pedestrian
fatalities per year; and NHTSA says about 4400 pedestrian fatalities
per year. Why the discrepancy between WISQARS and NHTSA? Deaths are
usually relatively easy to count.

While we're at it, WISQARS estimates about 1700 motorcyclist
fatalities annually. NHTSA says about 5300. That's exactly the same
event, with someone (probably WISQARS) having a 3:1 error.

One possible explanation is that the WISQARS data is quite soft. I
note that for non-fatal injuries, they give confidence intervals
(which emphasizes it's based on extrapolations from sampling, not
actual counts). Their 95% confidence interval for cyclist
hospitalizations is 13,700 to 36,900. For pedestrians, it's 12,500 to
42,100. In other words, their data means there _could_ be 36,900
cyclists hospitalized per year, vs. just 12,500 pedestrians; but
looking at the fatality data, I think it's much likelier to got the
other way, that is, 42,000 pedestrians vs. 13,700 cyclists.


Bicyclists represent about 10% of serious injuries in the group you
mentioned.

By any reasonable estimation bicyclists must have the worst per-hour
rate of serious injury.

I don't think that's been demonstrated at all. But thanks for yet
another "Bicycling is DANGEROUS!" technique!

So, what motivates cyclists to spend so much time trying to prove that
cycling is very dangerous?

- Frank Krygowski

On Nov 22, 7:22*am, "Duane Hebert" wrote:
"RobertH" wrote in message

By any reasonable estimation bicyclists must have the worst per-hour
rate of serious injury.

Again, I don't believe that's been proven at all.

That's why they came up with the "per miles traveled" criteria.

"They" are people who study safety of transport, Duane. It's not some
conspiracy by people who like to ride bikes. You can find per-mile
data on the safety of buses, trains, airplanes, ferry boats, etc.

There is legitimate discussion on whether "per mile" or "per hour"
analysis is more useful. But both are used, and are useful for
certain types of comparisons.

The part that I don't get, is comparing pedestrian injuries by
number to cycling injuries by number. *What is the percentage
of people cycling? *What is the percentage of people walking?

Then you'd be asking for data per participant. That tends to be even
softer data. If a person walks for transportation many hundreds of
miles per year, but rides his bike twice, should his accident data
apply equally to pedestrians and cyclists? Or should there be some
minimum amount of riding to have someone count as a cyclist?

In any case, if you're showing this much curiosity, don't you think
it's time _you_ dug out some data and studied it? That would make
more sense than habitually excluding data others provide, with no
justification at all.

- Frank Krygowski

On Nov 22, 12:26*pm, Dan O wrote:
On Nov 21, 9:14 pm, Frank Krygowski wrote:

some
cyclists will rush to say "No, that's not right; cycling really is
dangerous!"

Well, there is danger, and you know it. *But nobody here is saying it
has to be *terribly* dangerous.

Dan, I'm not necessarily talking about people "here," whatever that
means. (Do we count the lurkers? Do we count those who drop in once
per month?)

But there absolutely are cyclists who will say, for example, "You can
get a head injury and die just riding in your driveway." There are
cyclists who say "The only way to ride is to pretend that you're
totally invisible" or "to pretend that every driver is out to kill
you."

I've heard cyclists say those things, and I've read them in print. If
they're not trying to convey terrible danger, what is the point of
such statements?

- Frank Krygowski

On 11/22/2010 3:25 PM, Frank Krygowski wrote:
On Nov 22, 7:22 am, "Duane wrote:
wrote in message

By any reasonable estimation bicyclists must have the worst per-hour
rate of serious injury.

Again, I don't believe that's been proven at all.

That's why they came up with the "per miles traveled" criteria.

"They" are people who study safety of transport, Duane. It's not some
conspiracy by people who like to ride bikes. You can find per-mile
data on the safety of buses, trains, airplanes, ferry boats, etc.

You know Frank, it's possible to question the stats that you
provide without claiming a conspiracy.

There is legitimate discussion on whether "per mile" or "per hour"
analysis is more useful. But both are used, and are useful for
certain types of comparisons.

Maybe but "per hour" makes more sense to me but that's not my point.
If you want to use "per miles cycled" to "per miles cycled" to
do comparisons across gender, across geographical areas etc, this
makes sense. But to compare per miles cycled to per miles walked
doesn't make sense to me.

The part that I don't get, is comparing pedestrian injuries by
number to cycling injuries by number. What is the percentage
of people cycling? What is the percentage of people walking?

Then you'd be asking for data per participant. That tends to be even
softer data. If a person walks for transportation many hundreds of
miles per year, but rides his bike twice, should his accident data
apply equally to pedestrians and cyclists? Or should there be some
minimum amount of riding to have someone count as a cyclist?

If you are concerned about the number of injuries per time riding a
bike, then I would say yes. But you just want to say that cycling
is less dangerous than walking. Are you surprised that people
question that?

In any case, if you're showing this much curiosity, don't you think
it's time _you_ dug out some data and studied it? That would make
more sense than habitually excluding data others provide, with no
justification at all.

Again, this started with you lambasting James when he questioned
some stats that you threw out. As far as justification, I simply
quoted some info from the report to which you referred me.

Just out of curiosity, why do you think the emergency medical
community (ER workers, police EMTs etc.) doesn't seem to agree
with your statistics?

On Nov 23, 7:31*am, Frank Krygowski wrote:

But there absolutely are cyclists who will say, for example, "You can
get a head injury and die just riding in your driveway."

Possible, though not probable.

*There are
cyclists who say "The only way to ride is to pretend that you're
totally invisible" or "to pretend that every driver is out to kill
you."

Not bad advice, Frank, couldn't agree more.

Never _expect_ a motorist to giveway. The moment you trust them to do
the right thing, you'll find yourself skimming over their bonnet and
on to the road. Been there, done that. Be prepared with an escape
route and be alert for them to do the wrong thing right in front of
you. To say _pretend_ you're invisible, or _pretend_ they're out to
kill you is a way of saying be prepared for the worst acts of failing
to giveway, and when it saves you from a nasty bingle you'll gain
confidence in your own ability and suddenly cycling in traffic isn't
so worrying.

You're an advocate of not riding in the door zone, aren't you? Well
if the motorists who open car doors are not _treated_ as though
they're trying to kill you, you'd expect them to look in their mirror
and not open a door in front of you, no?

I've heard cyclists say those things, and I've read them in print. *If
they're not trying to convey terrible danger, what is the point of
such statements?

The point is to prepare less savvy cyclists to the possible dangers
they'll face on a per ride basis, depending on where they ride.
Nothing wrong with that. Cycling involves dangers and circumstances
you don't get just driving a car. Cyclists should be made aware of
the potentially dangerous situations.

Tell me, is it not terribly dangerous to ride just a foot from the
parked cars?

JS.

On Nov 22, 1:16 pm, Frank Krygowski wrote:

Thanks. I don't understand the business about "transfers" (to where?)
but querying on just "hospitalizations" gives roughly similar numbers
in about the same proportions.

But we're running into some oddities in data here. That data
(apparently, national estimates computed from a small sampling of
hospitals) claims hospital admissions of cyclists are about equal to
hospital admissions of pedestrians.

Yet we know that ped fatalities greatly exceed cyclist fatalities.
There are roughly 5000 pedestrians, but only 700 cyclists killed per
year. (either from WISQARS or from NHTSA, via a different
mechanism.) How is it that cycling causes as many hospitalizations as
walking down the street, yet walkers get killed six or seven times as
often? The fatality counts for cyclists and peds aren't even close.
Walking causes far more deaths.

Walking doesn't cause deaths, so much, it's the getting hit by cars
while walking that does it.

Pedestrians twist and break ankles regularly but don't face too many
mechanisms of possible _serious injury_ other than collisions with
motor vehicles. Bicyclists, on the other hand, especially child
bicyclists, can get seriously injured very nicely without the help of
a vehicle. That's one possible explanation of the numbers. Roughly one
third of pedalcyclist hospital admissions are kids under 16.

Also, on fatalities: WISQARS says there are about 5300 pedestrian
fatalities per year; and NHTSA says about 4400 pedestrian fatalities
per year. Why the discrepancy between WISQARS and NHTSA? Deaths are
usually relatively easy to count.

There is a discrepancy between WISQARS and FARS for cyclist deaths as
well. I doubt WISQARS is adding deaths that didn't occur. I think what
happens is this: WISQARS is based on death certificates, whereas FARS
is based on police reports and/or state transportation records. So if
a kid falls off a bike in a driveway, or somebody wrecks fatally on a
mountain trail, or whatever, has a heart attack while hiking, it may
not make it into transportation records but may still be classified as
a pedalcyclist or pedestrian death in WISQARS. Also, it is possible
that many deaths are just plain misclassified by NHTSA/FARS or missed.

While we're at it, WISQARS estimates about 1700 motorcyclist
fatalities annually. NHTSA says about 5300. That's exactly the same
event, with someone (probably WISQARS) having a 3:1 error.

Not sure where you got the alleged 'estimate' but WISQARS fatality
reports only go up to 2007. And in 2007 they counted about 5,000
motorcyclist deaths.

On Nov 23, 7:53*am, Duane Hébert wrote:
On 11/22/2010 3:25 PM, Frank Krygowski wrote:

There is legitimate discussion on whether "per mile" or "per hour"
analysis is more useful. *But both are used, and are useful for
certain types of comparisons.

Maybe but "per hour" makes more sense to me but that's not my point.
If you want to use "per miles cycled" to "per miles cycled" to
do comparisons across gender, across geographical areas etc, this
makes sense. *But to compare per miles cycled to per miles walked
doesn't make sense to me.

I totally agree. Had this point out with Frank a while ago. He
focuses on statistics that help prove his point and ignores the rest
even if they make more sense. Obviously pedestrians only (generally)
die crossing the street, so if pedestrians didn't cross the road their
stats would look a whole lot better. Cyclists OTOH are forced to use
roads in most parts, so they're exposed to risk for more of the time
that they spend cycling.

Regards,
James.

On Nov 22, 3:53*pm, Duane Hébert wrote:
On 11/22/2010 3:25 PM, Frank Krygowski wrote:

There is legitimate discussion on whether "per mile" or "per hour"
analysis is more useful. *But both are used, and are useful for
certain types of comparisons.

Maybe but "per hour" makes more sense to me but that's not my point.
If you want to use "per miles cycled" to "per miles cycled" to
do comparisons across gender, across geographical areas etc, this
makes sense. *But to compare per miles cycled to per miles walked
doesn't make sense to me.

And yet, there have been people who have posted here, saying that
cycling is obviously dangerous because there are more fatalities per
mile for cycling than for riding in a car. At this point, I don't
remember exactly who made that argument and whether you were in the
discussion. But can I assume, then, that you'd discount any such
claim that cycling was more dangerous than motoring?



The part that I don't get, is comparing pedestrian injuries by
number to cycling injuries by number. *What is the percentage
of people cycling? *What is the percentage of people walking?

Then you'd be asking for data per participant. *That tends to be even
softer data. *If a person walks for transportation many hundreds of
miles per year, but rides his bike twice, should his accident data
apply equally to pedestrians and cyclists? *Or should there be some
minimum amount of riding to have someone count as a cyclist?

If you are concerned about the number of injuries per time riding a
bike, then I would say yes. *But you just want to say that cycling
is less dangerous than walking. *Are you surprised that people
question that?

I'm not at all surprised, because whenever someone says cycling is
_not_ dangerous, it tends to draw arguments and statements that say
things like "Of _course_ riding a bike is dangerous!" I'm not the
only author who has felt the need to write articles disputing the
"Danger! Danger!" hype.

In any case, if you're showing this much curiosity, don't you think
it's time _you_ dug out some data and studied it? *That would make
more sense than habitually excluding data others provide, with no
justification at all.

Again, this started with you lambasting James when he questioned
some stats that you threw out. * As far as justification, I simply
quoted some info from the report to which you referred me.

You said, essentially, that the data was no good because it was too
old. Yet you provided no data that was more current. It's easy to
stand at the sidelines and criticize those doing the work, Duane.
It's harder to actually do the work. Why not try?

Just out of curiosity, why do you think the emergency medical
community (ER workers, police EMTs etc.) doesn't seem to agree
with your statistics?

Do they disagree with my statistics? If they were actually doing that
with any rationality, they'd be saying "No, those data are wrong, here
are the correct numbers..." I don't recall that happening.

But as it happens, we have an ER physician in our extended family. He
seems to be in general agreement with almost everything I post here.
I've also had conversations (real life, or online) with brain injury
specialists who have admitted that they get almost no cyclists as
patients.

Aside from that, if what you really mean is that some EMT workers,
etc. question my conclusions (rather than statistics), I'd say people
doing medical work are as prone to mistakes in judgment as anyone
else. It's not hard to find medical research papers with rather
obvious mistakes and bias. Examples on request.

- Frank Krygowski