The biggest and best bicyclist/accident study ever: helmets saved lives

Here is a really thorough and statistically ultra-respectable report
about cycling casualties and serious injuries in New York. Download it
from:
http://www.nyc.gov/html/doh/download...ike-report.pdf
What is so good about it this particular report that it isn't based
on a sample, it is an entire universe, all the deaths on the roads in
one of the largest cities in the world. And it isn't a snapshot, it
covers a ten-year period. And it doesn't have to guess at causes: it
had full access to the police reports and hospital reports because it
was compiled for, among others, the Police Commissioner and the Health
Commissioner. This is the sort of report that no one in private
industry can ever afford to make. (I should know; at one stage I
controlled market research budgets totalling 160mUSD per annum, and I
sure as hell didn't ever have six or eight or ten employees sitting
around idle that I could assign for a year or two or three to slugging
through ten years of police accident scene reports, hospital filing
cabinets, etc. Just for expressing such a desire, I would have been
given over to the men in white coats! We're talking really major work
here.)

Something else that is brilliant about this report is that its
conclusions are humbly drawn by a statistician who never once
overreaches himself. He never goes beyond the self-evident and the
obvious, because with such statistics -- the entire universe, I say
again! -- he doesn't have to take any chances: he can stick to
certainties. Here are some certainties from the report:

• Only one fatal crash (out of 225) with a motor vehicle occurred when
a bicyclist was in a marked bicycle lane.

Implication: Separate bicycle facilities work.

• Most fatal crashes (74%) involved a head injury.
• Nearly all bicyclists who died (97%) were not wearing a helmet.

These two facts together are already an argument for wearing a helmet.
But, when we add the next one, the argument for wearing a helmet
becomes very strong indeed:

• Compare the very low level of helmet use in fatal crashes (3%) to
that in non-fatal crashes leading to serious injury (13%).

Implication: As we already know that head injuries are involved in
74% of fatalities, this suggests strongly that not wearing a helmet
may be particularly dangerous. It looks like wearing a helmet saved
roundabout 33 cyclists or so (of the 333 seriously injured for whom
helmet use is known) from dying. Furthermore we can say that at least
ten per cent of those who did die, say 22 people, could well have
lived if they had worn a helmet.

The difference is probably not big enough to support mandatory helmet
laws in the States (1) but the writing is on the wall, I think.

Andre Jute
Get a bicycle. You will not regret it. If you live -- Mark Twain

(1) In European countries where there is a major bike culture,
cyclists ride differently and drivers drive differently, and elsewhere
there are too few cyclists to attract the attention of the European
Parliament and EU Commission, so there is no need for such a law. But
if there were a need, such a thorough report would very quickly lead
to legislation and regulation.

On Oct 30, 5:05*pm, Andre Jute wrote:
Here is a really thorough and statistically ultra-respectable report
about cycling casualties and serious injuries in New York. Download it
from:
*http://www.nyc.gov/html/doh/download...ike-report.pdf
*What is so good about it this particular report that it isn't based
on a sample, it is an entire universe, all the deaths on the roads in
one of the largest cities in the world. And it isn't a snapshot, it
covers a ten-year period. And it doesn't have to guess at causes: it
had full access to the police reports and hospital reports because it
was compiled for, among others, the Police Commissioner and the Health
Commissioner. This is the sort of report that no one in private
industry can ever afford to make. (I should know; at one stage I
controlled market research budgets totalling 160mUSD per annum, and I
sure as hell didn't ever have six or eight or ten employees sitting
around idle that I could assign for a year or two or three to slugging
through ten years of police accident scene reports, hospital filing
cabinets, etc. Just for expressing such a desire, I would have been
given over to the men in white coats! We're talking really major work
here.)

Something else that is brilliant about this report is that its
conclusions are humbly drawn by a statistician who never once
overreaches himself. He never goes beyond the self-evident and the
obvious, because with such statistics -- the entire universe, I say
again! -- he doesn't have to take any chances: he can stick to
certainties. Here are some certainties from the report:

• Only one fatal crash (out of 225) with a motor vehicle occurred when
a bicyclist was in a marked bicycle lane.

Implication: Separate bicycle facilities work.

• Most fatal crashes (74%) involved a head injury.
• Nearly all bicyclists who died (97%) were not wearing a helmet.

These two facts together are already an argument for wearing a helmet.
But, when we add the next one, the argument for wearing a helmet
becomes very strong indeed:

• Compare the very low level of helmet use in fatal crashes (3%) to
that in non-fatal crashes leading to serious injury (13%).

Implication: *As we already know that head injuries are involved in
74% of fatalities, this suggests strongly that not wearing a helmet
may be particularly dangerous. It looks like wearing a helmet saved
roundabout 33 cyclists or so (of the 333 seriously injured for whom
helmet use is known) from dying. Furthermore we can say that at least
ten per cent of those who did die, say 22 people, could well have
lived if they had worn a helmet.

The difference is probably not big enough to support mandatory helmet
laws in the States (1) but the writing is on the wall, I think.

Andre Jute
*Get a bicycle. You will not regret it. If you live -- Mark Twain

(1) In European countries where there is a major bike culture,
cyclists ride differently and drivers drive differently, and elsewhere
there are too few cyclists to attract the attention of the European
Parliament and EU Commission, so there is no need for such a law. But
if there were a need, such a thorough report would very quickly lead
to legislation and regulation.

On Oct 30, 7:08*am, rover109 wrote:
On Oct 30, 5:05*pm, Andre Jute wrote:



Here is a really thorough and statistically ultra-respectable report
about cycling casualties and serious injuries in New York. Download it
from:
*http://www.nyc.gov/html/doh/download...ike-report.pdf
*What is so good about it this particular report that it isn't based
on a sample, it is an entire universe, all the deaths on the roads in
one of the largest cities in the world. And it isn't a snapshot, it
covers a ten-year period. And it doesn't have to guess at causes: it
had full access to the police reports and hospital reports because it
was compiled for, among others, the Police Commissioner and the Health
Commissioner. This is the sort of report that no one in private
industry can ever afford to make. (I should know; at one stage I
controlled market research budgets totalling 160mUSD per annum, and I
sure as hell didn't ever have six or eight or ten employees sitting
around idle that I could assign for a year or two or three to slugging
through ten years of police accident scene reports, hospital filing
cabinets, etc. Just for expressing such a desire, I would have been
given over to the men in white coats! We're talking really major work
here.)

Something else that is brilliant about this report is that its
conclusions are humbly drawn by a statistician who never once
overreaches himself. He never goes beyond the self-evident and the
obvious, because with such statistics -- the entire universe, I say
again! -- he doesn't have to take any chances: he can stick to
certainties. Here are some certainties from the report:

• Only one fatal crash (out of 225) with a motor vehicle occurred when
a bicyclist was in a marked bicycle lane.

Implication: Separate bicycle facilities work.

• Most fatal crashes (74%) involved a head injury.
• Nearly all bicyclists who died (97%) were not wearing a helmet.

These two facts together are already an argument for wearing a helmet.
But, when we add the next one, the argument for wearing a helmet
becomes very strong indeed:

• Compare the very low level of helmet use in fatal crashes (3%) to
that in non-fatal crashes leading to serious injury (13%).

Implication: *As we already know that head injuries are involved in
74% of fatalities, this suggests strongly that not wearing a helmet
may be particularly dangerous. It looks like wearing a helmet saved
roundabout 33 cyclists or so (of the 333 seriously injured for whom
helmet use is known) from dying. Furthermore we can say that at least
ten per cent of those who did die, say 22 people, could well have
lived if they had worn a helmet.

The difference is probably not big enough to support mandatory helmet
laws in the States (1) but the writing is on the wall, I think.

Andre Jute
*Get a bicycle. You will not regret it. If you live -- Mark Twain

(1) In European countries where there is a major bike culture,
cyclists ride differently and drivers drive differently, and elsewhere
there are too few cyclists to attract the attention of the European
Parliament and EU Commission, so there is no need for such a law. But
if there were a need, such a thorough report would very quickly lead
to legislation and regulation.

I agree that little more need be said.
DR

Andre Jute writes:

Here is a really thorough and statistically ultra-respectable report
about cycling casualties and serious injuries in New York. Download it
from:
http://www.nyc.gov/html/doh/download...ike-report.pdf

• Only one fatal crash (out of 225) with a motor vehicle occurred when
a bicyclist was in a marked bicycle lane.

Implication: Separate bicycle facilities work.

I wouldn't draw that conclusion. Consider that 89% of crashes occurred
at or near intersections. Marked bike lanes generally do not extend
through intersections---consequently, a high percentage of all crashes
would not be in a marked bike lane even if the road had bike lanes.
What is the percentage of roadway with marked bike lanes in New York
city?

--
Joe Riel

On Sun, 30 Oct 2011 13:23:11 -0700, Joe Riel wrote:

What is the percentage of roadway with marked bike lanes in New York
city?

This might help:
http://www.nycbikemaps.com/maps/
http://www.nycbikemaps.com/maps/google-earth-bike-map/
and:
http://www.nyc.gov/html/dot/html/bicyclists/bikenetwork.shtml
http://www.nyc.gov/html/dot/downloads/pdf/bikeroutedetailsfy07-fy11.pdf
Unfortunately, neither the summary, or the original report bothers to
mention the length of existing bike paths, chosing only to mention the
length added. Still, 200 miles of exclusive bike lanes, and 82 miles
of shared lanes ADDED in the last 5 years is non-trivial.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Oct 30, 8:23*pm, Joe Riel wrote:
Andre Jute writes:
Here is a really thorough and statistically ultra-respectable report
about cycling casualties and serious injuries in New York. Download it
from:
*http://www.nyc.gov/html/doh/download...ike-report.pdf
• Only one fatal crash (out of 225) with a motor vehicle occurred when
a bicyclist was in a marked bicycle lane.

Implication: Separate bicycle facilities work.

I wouldn't draw that conclusion. *Consider that 89% of crashes occurred
at or near intersections. *Marked bike lanes generally do not extend
through intersections---consequently, a high percentage of all crashes
would not be in a marked bike lane even if the road had bike lanes.
What is the percentage of roadway with marked bike lanes in New York
city? *

--
Joe Riel

That bike lanes have not been thoroughly carried through is not a
reason for rejecting evidence that where they exist they work. It is a
reason for instituing bike lanes at high risk locations to save more
lives. Here are some possible examples of solutions for intersections:

1. Bicycle and pedestrian flyovers. (That other day in Cork I saw a
whole convention of wheelchair users use a bridge over a motorway and
stopped to talk to them. it was the first time in their lives that any
of the had ever been south of the motorway...)

2. Lights that stop motor traffic for bicycle-only crossing periods.

3. Rearranging the "yellow box" (exclusion) zones so that bicycles
stop on front of cars, and go first when the lights change.

4. Dividing roads between cars-only, bikes-only and pedestrian-only.
Bike malls, I love the idea already, even though i just had it.

5. This is before the expansion in the links Jeff offers.

6. More ideas if we'll put our minds in gear instead of being
mindlessly negative as a first impulse.

Andre Jute
My mind is in gear. Is yours?

On Oct 30, 9:01*pm, Jeff Liebermann wrote:
On Sun, 30 Oct 2011 13:23:11 -0700, Joe Riel wrote:
What is the percentage of roadway with marked bike lanes in New York
city? *

This might help:
http://www.nycbikemaps.com/maps/
http://www.nycbikemaps.com/maps/google-earth-bike-map/
and:
http://www.nyc.gov/html/dot/html/bicyclists/bikenetwork.shtml
http://www.nyc.gov/html/dot/downloads/pdf/bikeroutedetailsfy07-fy11.pdf
Unfortunately, neither the summary, or the original report bothers to
mention the length of existing bike paths, chosing only to mention the
length added. *Still, 200 miles of exclusive bike lanes, and 82 miles
of shared lanes ADDED in the last 5 years is non-trivial.

--
Jeff Liebermann * *
150 Felker St #D * *http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann * * AE6KS * *831-336-2558

It would be really very nice to follow up such a massive, and
massively indicative, and massively reliable, study. But the cost must
have been enormous, so I don't hold out much hope.

Anyway, the lesson has been learned, except for incorrigbles like
Krygowski, who are anti-helmet zealots as a matter of religious
conviction, so the politicians and their professional advisors
probably feel money for research should be spent elsewhere now,
perhaps on traffic patterns as they change with more bike lanes and
more cyclists.

Andre Jute
Not a political animal -- thank God!

On Sun, 30 Oct 2011 18:01:13 -0700 (PDT), Andre Jute
wrote:

It would be really very nice to follow up such a massive, and
massively indicative, and massively reliable, study. But the cost must
have been enormous, so I don't hold out much hope.

Assorted NYC bicycling statistics:
http://www.nyc.gov/html/dot/html/bicyclists/bikestats.shtml
http://www.nyc.gov/html/dcp/html/transportation/td_projectbicycle.shtml

Speaking of burning public money, some group sued to block the
conversion of a traffic lane into a bicycle lane in New Yuck.
http://www.nyc.gov/html/dot/html/bicyclists/prospectparkwest.shtml
In order to justify the change, NYC apparently collected some
before/after statistics, all of which indicate impressive
improvements.
http://www.nyc.gov/html/dot/downloads/pdf/20110120_ppw.pdf
http://www.nyc.gov/html/dot/downloads/pdf/20110120_ppw_data.pdf
(with data). I suspect that some of the increase in bicycle traffic
was the result of attracting riders from parallel streets, that are
now comparatively unsafe after the lane conversion. Data was also not
collected year round, making seasonal variations another source of
error. Sigh.





--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 30 Oct 2011 13:23:11 -0700, Joe Riel wrote:

Andre Jute writes:

Here is a really thorough and statistically ultra-respectable report
about cycling casualties and serious injuries in New York. Download it
from:
http://www.nyc.gov/html/doh/download...ike-report.pdf

• Only one fatal crash (out of 225) with a motor vehicle occurred when
a bicyclist was in a marked bicycle lane.

Implication: Separate bicycle facilities work.

I wouldn't draw that conclusion. Consider that 89% of crashes occurred
at or near intersections. Marked bike lanes generally do not extend
through intersections---consequently, a high percentage of all crashes
would not be in a marked bike lane even if the road had bike lanes.
What is the percentage of roadway with marked bike lanes in New York
city?

It is amazing the information that can be obtained from this report.

For example. "7% of fatal crashes occurred on limited access highways,
where bicycling is prohibited."

An attempt was made to classify the contributing factors for each
accident with some 1899 ( 55%) of accidents categorized. Of these
accidents where a contributing factor could be assigned (55% of all
accidents) the Vehicle Only amounted to some 1222 (35%) of categorized
accidents while Bicycle Only amounted to some 455 (13%) (with 6% to a
combination of vehicle and bicycle).

Of the Vehicle Only category the most common attributing causes were
classified as Driver inattention (31%), unspecified human error (29%),
failure to yield (9%), speeding (4%) and disregarding traffic controls
(4%)

Of the bicycle only category the most common were a bicyclist crossing
into a vehicle path 84%, disregarding traffic controls (8%), failure
to yield (2%), speeding (1%) and turning improperly (1%).

It would appear that of the Vehicle Only category some 207.58
accidents amounting to 16.9% of the Vehicle Only classification were
due to Highway Code violations.

Of the Bicycle Only classification some 436 (96%) were due to Highway
Code violations.

As 15 (7%) of bicycle fatalities occurred on limited access highways,
where bicycling is prohibited and 436 (96%) of accidents that were
categorized as a Bicycle Only contributing factor were acts in
violation of Highway Codes it appears that in any discussion of
bicycle safety there may just be significant contributing factors
other then safety helmets.



--
John B.

On Oct 31, 3:13*am, John B. wrote:
On Sun, 30 Oct 2011 13:23:11 -0700, Joe Riel wrote:
Andre Jute writes:

Here is a really thorough and statistically ultra-respectable report
about cycling casualties and serious injuries in New York. Download it
from:
*http://www.nyc.gov/html/doh/download...ke-report..pdf

• Only one fatal crash (out of 225) with a motor vehicle occurred when
a bicyclist was in a marked bicycle lane.

Implication: Separate bicycle facilities work.

I wouldn't draw that conclusion. *Consider that 89% of crashes occurred
at or near intersections. *Marked bike lanes generally do not extend
through intersections---consequently, a high percentage of all crashes
would not be in a marked bike lane even if the road had bike lanes.
What is the percentage of roadway with marked bike lanes in New York
city? *

It is amazing the information that can be obtained from this report.

For example. "7% of fatal crashes occurred on limited access highways,
where bicycling is prohibited."

An attempt was made to classify the contributing factors for each
accident with some 1899 ( 55%) of accidents categorized. Of these
accidents *where a contributing factor could be assigned (55% of all
accidents) the Vehicle Only amounted to some 1222 (35%) of categorized
accidents while Bicycle Only amounted to some 455 (13%) (with 6% to a
combination of vehicle and bicycle).

Of the Vehicle Only category the most common attributing causes were
classified as Driver inattention (31%), unspecified human error (29%),
failure to yield (9%), speeding (4%) and disregarding traffic controls
(4%) *

Of the bicycle only category the most common were a bicyclist crossing
into a vehicle path 84%, disregarding traffic controls (8%), failure
to yield (2%), speeding (1%) and turning improperly (1%).

It would appear that of the Vehicle Only category some 207.58
accidents amounting to 16.9% of the Vehicle Only classification were
due to Highway Code violations.

Of the Bicycle Only classification some 436 (96%) were due to Highway
Code violations.

As 15 (7%) of bicycle fatalities occurred on limited access highways,
where bicycling is prohibited and 436 (96%) of accidents that were
categorized as a Bicycle Only contributing factor were acts in
violation of Highway Codes it appears that in any discussion of
bicycle safety there may just be significant contributing factors
other then safety helmets.

--
John B.

It's an amazing report indeed, not least for its scale.

As we're considering the efficacy of bicycle helmets, I don't see the
need for your plan to exclude from the tally bicyclists who weren't
100% compliant with any and all known or future or possible laws. That
would be like testing the efficacy of seat belts by excluding cars
with broken taillights from the test.

Andre Jute
This is so simple, we could let Krygowski do it