"R15757" <
[email protected]> wrote in message
news:
[email protected]...
> Riley Geary wrote:
>
> >If you define "seeking medical attention" as showing up at an ER, the CDC
> >data would suggest the ratio with respect to fatalities is more like 600
> >or
> >700-to-1.
>
> "Seeking medical attention" means just that.
> The NEISS estimates a half million outpatients
> seeking treatment for a bicycle-related
> injury in addition to the half million ER visits.
>
> >>The number of ALL injuries is unknown
> >> and unknowable, but a 5,000-to-1 ratio of total injuries-to-fatalities
> >> seems reasonable. The ratio of hospitalizations to fatalities would
> >> be what? About 60-to-1?
> >>
> >
> >No, more like 25-to-1. The ratio of hospitalizations to fatalities for
> >motor vehicle occupants is only about 6-to-1, and just 4-to-1 for
> >pedestrians. OTOH, the ratio for non-traffic-related bicycle
> >hospitalizations to fatalities is probably close to 50-to-1. Keep in
mind
> >this simply demonstrates that even among the more serious injuries
requiring
> >hospitalization, cyclists are much less likely to die from their injuries
> >than either motor vehicle occupants or pedestrians (this is generally
> >considered a good thing, though I suppose it may depend on your
> >perspective).
>
> I want to be clear here. Are you saying that
> motor vehicle occupants are hospitalized at
> 4 times the rate of cyclists who have been
> injured in a car-bike accident? Or of cyclists
> who have been injured in all types of bicycle
> accidents? Big difference obviously.
I think you've got that backward, since overall cyclists have a
hospitalization-to-fatality rate about 4 times that of motor vehicle
occupants, not the other way round. For traffic-related cycling crashes,
the ratio of hospitalizations to fatalities is about 22-to-1. The reason
it's so close to the overall figure is because while about 75% of all
bicycle-related hospitalizations are due to traffic-related crashes,
something like 85% of all bicycle-related fatalities are similarly
traffic-related.
I should point out here that there is a considerable problem with the CDC
fatality data in the distribution between traffic-related and
non-traffic-related causes--due primarily to coding changes that took place
when the CDC went from the IDC-9 definitions used from 1979-98 to the
revised IDC-10 definitions it has been using since 1999. Prior to 1999, the
portion of cycling fatalities coded as non-traffic-related slowly rose from
about 10% to about 15%, reflecting the changing demographics of the cycling
population, the increasing popularity of off-road cycling, etc, but then
jumped to 23% during 1999-2000, increased to 26% in 2001, and 28% as of
2002.
This makes no sense given that the non-traffic-related portion of cycling
hospitalizations also currently stand at about 25%, while they constitute
nearly half of all cycling-related trips to an ER. Likewise, CDC
traffic-related cycling fatalities generally ran 6-7% under the
corresponding FARS numbers prior to 1999, but have been running about 18%
under the FARS numbers since 1999. Conversely, total CDC cycling-related
fatalities have averaged about 6-7% over FARS data, both before and after
1999--except most recently in 2002, when they ran 15% over the FARS numbers.
This strongly suggests that the CDC has traditionally had a problem
miscoding some traffic-related cycling fatalities as non-traffic-related (or
possibly even as non-cycling fatalities), but the problem became much worse
when they went from IDC-9 to IDC-10 codes.
>
> It seems that the rate of hospitalization
> would be similar for all parties involved in
> an accident with a motor vehicle, whether the
> injured party be on a bike, on foot, or a
> passenger in a car. That is my suspicion
> anyway.
There are important physical differences involved in traffic crashes that
influence potential outcomes for the victims involved depending on whether
they are pedestrians, bicyclists, or motor vehicle occupants. MVO's
obviously have the external protection offered by the vehicle itself in a
crash, along with the substantial safety benefits offered by safety belts
and (to a much lesser degree) air bags--which helps create a threshold
effect where most potential minor to moderate injuries are avoided
altogether, and even serious to potentially fatal injuries are moderated to
a significant degree.
In terms of the differences between cyclists and pedestrians, cyclists have
a higher center-of-gravity, are less likely to be involved in high speed or
nighttime collisions, and are much more likely to be just struck a glancing
blow relative to pedestrians. For example, one of the most common car-bike
collision types involves a motorist passing and then cutting off a cyclist
with a right turn, either at an intersection or commercial driveway, causing
the cyclist to hit the side of the car at a fairly shallow angle and with a
fairly low closing velocity (~10 mph?), and usually resulting in nothing
worse than a fall from the bike. Put a pedestrian in place of a cyclist in
that sort of situation and they're likely to face a full-frontal impact by a
3000+ lb vehicle traveling at 20+ mph, with results generally much more
severe than for the cyclist. The higher center-of-gravity also means a
cyclist is much more likely to roll over the hood of an impacting vehicle
rather than end up under its wheels.
>
> >...but then couch sitters tend to suffer from a whole range of
> >serious health risks later in life due to their >sedentary lifestyle;
>
> Yes of course. But everybody sits on the couch,
> even avid cyclists. When we do so, we are at much
> less risk of accidental injury than when we are
> riding our bikes.
>
> >and
> >even for traffic-related injuries, cyclists suffer far fewer fatalities
> >relative to either serious injuries (~1 per 22 hospitalizations) or all
> >injuries for which medical attention is sought (~1 per 400 trips to the
> >ER)
> >compared to either motor vehicle occupants (~1 per 85 ER visits) or
> >pedestrians (~1 per 28 ER visits).
>
> "Traffic-related injuries?" So all those would
> involve contact with a motor vehicle then?
By the definition used by both the CDC and FARS, yes.
> Otherwise it seems like you are just giving
> another stat that shows that cyclists face
> a greater likelihood of minor injury compared
> to their driving counterparts (due to solo wipeouts),
> IN ADDITION to facing a similar risk with regard
> to motor-vehicle involved accidents.
Not exactly. Cyclists face an enormously greater risk of minor injury
relative to either motor vehicle occupants or pedestrians, but not
necessarily when it comes to serious or fatal injuries.
Of course, the same could just as easily be said about basketball, soccer,
skiing, ice skating, or any number of other outdoor activities. If someone
finds the prospect of an occasional bit of road rash or other minor injury
too terrifying to contemplate, then they probably should resign themselves
to a life of couch sitting.
>
> >Granted, even though a disproportionate number of those ER visits are due
> >to
> >juvenile cyclists, and thus have little real relevance to adult cycling
> >conditions.
>
> Very true, although I suspect this is true even
> if the kids' injuries are culled out. A disproportionate
> number of the "trivial" ER visits belong to kids as well.
> Adults don't go to the ER for "skinned knees."
OK, for traffic-related injuries suffered by adult cyclists 16 or older, we
have 1 fatality per ~17 hospitalizations and ~250 trips to the ER.
>
> >> But "pedestrian
> >> accidents" (unintentional falls while walking) are by far the
> >> number one cause of ER visits across all age groups. Pedestrians
> >> in the ER are hospitalized far less often than cyclists.
> >>
> >
> >Not according to the CDC data--unless you're including
> >non-transportation-related falls around the home, >etc.
>
> Well, yeah, we include non-transportation-
> related cycling injuries don't we? Or do
> we simply classify ALL cycling accidents as
> "traffic-related?"
No, but nearly all cycling injuries are classified as transportation-related
since the bicycle itself is considered a (non-motorized) vehicle--the
difference here is whether a motor vehicle is involved or not (which means
bike-only, bike-bike, bike-ped, and similar crashes are all considered
transportation-related, but not traffic-related, at least according to FARS
and CDC criteria). The only exception would be for any injuries sustained
while making repairs or otherwise using a bike in a non-transportation
capacity (e.g. having a parked bike fall on you rather than you falling off
a bicycle in motion).
> If you look at the CDC
> data (which I linked to from your site--great
> resource, thanks), you see that unintentional
> falls while walking around (in the park, across
> the street, in the home, whatever) are the
> number one cause of injury across all age groups.
Very true, but most of those are actually falls around the home (e.g.
falling off a ladder, slipping in the bathtub, tripping on a rug, falling
out of bed, etc) rather than falls associated with walking somewhere. It's
also worth pointing out that unlike the case with cycling injuries, serious
injuries associated with simple falls are overwhelmingly associated with the
elderly portion of our population--over 2/3 of such hospitalizations and
about 3/4 of such injuries resulting in death occur to those 65 or older
(but less than 1/4 of all such ER visits).
>
> >Total ER trips by
> >pedestrians (as defined by the CDC, both traffic-related and
> >non-traffic-related) are only about 1/3 the number of bicycle-related ER
> >trips (~175k vs ~500k/year), even though pedestrians account for slightly
> >more total hospitalizations than bicyclists (~24k vs ~19k/year), and
roughly
> >8 times as many fatalities (~6000 vs ~750/year). But then, that is the
> >sort
> >of ratio relationship we would expect where one type of activity tends to
> >produce a much larger fraction of serious to fatal injuries compared to
> >some
> >other activity.
>
> Well, you have to define "pedestrian" very
> narrowly to get that ratio.
>
Granted. It would be nice if the CDC provided a breakout of
"non-transportation" pedestrian injuries resulting from simple falls, but
the online database doesn't appear to offer that option.
Riley Geary
