Bicycle DRL Study. 30%-50% Crash Reduction

I know how some people dislike any statements that are based on actual
data, but the data is pretty clear.

There is one case-controlled study on bicycle DRLs.

From OECD, International Transport Forum (2013), Cycling, Health and
Safety
https://books.google.com.au/books?id=LvthAgAAQBAJ&pg=PA168&hl=en#v=onepage&q&f =false:
"The safety effect of daytime running lights on bicycles was tested in a
Danish study in 2005 (Madsen 2006). Nearly 2,000 cyclists in the town of
Odense used the new induction lights (flashing type) for one year with,
while 2,000 others continued with ordinary bike lights, which were only
switched on during dark hours. The accident frequencies of the two
groups (based on self-reported accidents) were then compared and analysed.

The main result was that use of daytime running lights was associated
with a reduction of the number of crashes by more than 30%. The number
of related crashes (crashes in daylight and with a counterpart)
decreased by 50% approximately. Both results are statistically
signi�cant. There are indications that the study may have not controlled
for all factors - for instance it is unclear to what extent the control
group’s crashes included single vehicle crashes (this type of crash is
hardly influenced use of induction lights). Also, the study makes no
�nding as to the safety effect of flashing versus steady lights."

As you can see, the data on bicycle DRLs is actually much more
compelling than the data on vehicle DRLs! And they weren't creating
bogus studies or intentionally misinterpreting data as one organization
we know of is so fond of doing!

But the reduction in crashes is not the only benefit of DRLs. The other
benefit is how bicycle DRLs shape driver behavior by making cyclists
much more conspicuous in the daytime.

On 7/11/2015 10:57 AM, sms wrote:
I know how some people dislike any statements that are based on actual
data, but the data is pretty clear.

There is one case-controlled study on bicycle DRLs.

From OECD, International Transport Forum (2013), Cycling, Health and
Safety
https://books.google.com.au/books?id=LvthAgAAQBAJ&pg=PA168&hl=en#v=onepage&q&f =false:
"The safety effect of daytime running lights on bicycles was tested in a
Danish study in 2005 (Madsen 2006). Nearly 2,000 cyclists in the town of
Odense used the new induction lights (flashing type) for one year with,
while 2,000 others continued with ordinary bike lights, which were only
switched on during dark hours. The accident frequencies of the two
groups (based on self-reported accidents) were then compared and analysed.

The main result was that use of daytime running lights was associated
with a reduction of the number of crashes by more than 30%. The number
of related crashes (crashes in daylight and with a counterpart)
decreased by 50% approximately. Both results are statistically
signi�cant. There are indications that the study may have not controlled
for all factors - for instance it is unclear to what extent the control
group’s crashes included single vehicle crashes (this type of crash is
hardly influenced use of induction lights). Also, the study makes no
�nding as to the safety effect of flashing versus steady lights."

As you can see, the data on bicycle DRLs is actually much more
compelling than the data on vehicle DRLs! And they weren't creating
bogus studies or intentionally misinterpreting data as one organization
we know of is so fond of doing!

But the reduction in crashes is not the only benefit of DRLs. The other
benefit is how bicycle DRLs shape driver behavior by making cyclists
much more conspicuous in the daytime.

Have you actually read the study? I have.

That was the study that found that the users of daytime running lights
had fewer crashes of ALL types, including those types of crashes where
DRLs should have made no difference whatsoever. In fact, DRL users even
had far fewer solo falls off their bikes!

We've mentioned this already. It's very much analogous to the
pro-helmet paper that claimed 85% reduction in head injuries among
helmet wearers, but which hid the fact that their data also showed a 75%
reduction in leg injuries among helmet wearers.

In both cases, it seems obvious that the bulk of the purported benefit
was due to changes in cyclist behavior, not due to the actual
"protective" device.

--
- Frank Krygowski

On Saturday, July 11, 2015 at 4:30:24 PM UTC+1, Frank Krygowski wrote:
On 7/11/2015 10:57 AM, sms wrote:
I know how some people dislike any statements that are based on actual
data, but the data is pretty clear.

There is one case-controlled study on bicycle DRLs.

From OECD, International Transport Forum (2013), Cycling, Health and
Safety
https://books.google.com.au/books?id=LvthAgAAQBAJ&pg=PA168&hl=en#v=onepage&q&f =false:
"The safety effect of daytime running lights on bicycles was tested in a
Danish study in 2005 (Madsen 2006). Nearly 2,000 cyclists in the town of
Odense used the new induction lights (flashing type) for one year with,
while 2,000 others continued with ordinary bike lights, which were only
switched on during dark hours. The accident frequencies of the two
groups (based on self-reported accidents) were then compared and analysed.

The main result was that use of daytime running lights was associated
with a reduction of the number of crashes by more than 30%. The number
of related crashes (crashes in daylight and with a counterpart)
decreased by 50% approximately. Both results are statistically
signi�cant. There are indications that the study may have not controlled
for all factors - for instance it is unclear to what extent the control
group’s crashes included single vehicle crashes (this type of crash is
hardly influenced use of induction lights). Also, the study makes no
�nding as to the safety effect of flashing versus steady lights."

As you can see, the data on bicycle DRLs is actually much more
compelling than the data on vehicle DRLs! And they weren't creating
bogus studies or intentionally misinterpreting data as one organization
we know of is so fond of doing!

But the reduction in crashes is not the only benefit of DRLs. The other
benefit is how bicycle DRLs shape driver behavior by making cyclists
much more conspicuous in the daytime.

Have you actually read the study? I have.

That was the study that found that the users of daytime running lights
had fewer crashes of ALL types, including those types of crashes where
DRLs should have made no difference whatsoever. In fact, DRL users even
had far fewer solo falls off their bikes!

We've mentioned this already. It's very much analogous to the
pro-helmet paper that claimed 85% reduction in head injuries among
helmet wearers, but which hid the fact that their data also showed a 75%
reduction in leg injuries among helmet wearers.

In both cases, it seems obvious that the bulk of the purported benefit
was due to changes in cyclist behavior, not due to the actual
"protective" device.

--
- Frank Krygowski

Okay, these are positive, beneficial psychosomatic effects. I'll take them. Anything that reduces injuries to cyclists is good.

Andre Jute

On 7/11/2015 4:26 PM, Andre Jute wrote:
On Saturday, July 11, 2015 at 4:30:24 PM UTC+1, Frank Krygowski wrote:


Have you actually read the study? I have.

That was the study that found that the users of daytime running lights
had fewer crashes of ALL types, including those types of crashes where
DRLs should have made no difference whatsoever. In fact, DRL users even
had far fewer solo falls off their bikes!

We've mentioned this already. It's very much analogous to the
pro-helmet paper that claimed 85% reduction in head injuries among
helmet wearers, but which hid the fact that their data also showed a 75%
reduction in leg injuries among helmet wearers.

In both cases, it seems obvious that the bulk of the purported benefit
was due to changes in cyclist behavior, not due to the actual
"protective" device.

--
- Frank Krygowski

Okay, these are positive, beneficial psychosomatic effects. I'll take them. Anything that reduces injuries to cyclists is good.

https://www.youtube.com/watch?v=lDWNPL8a_6c
If your bike doesn't have a six foot tall flag made of lights, you're
not safe enough.

Even if you've already installed _all_ of these:
http://tinyurl.com/safe-as-can-be


--
- Frank Krygowski

On Saturday, July 11, 2015 at 5:09:14 PM UTC-4, Frank Krygowski wrote:
On 7/11/2015 4:26 PM, Andre Jute wrote:
On Saturday, July 11, 2015 at 4:30:24 PM UTC+1, Frank Krygowski wrote:


Have you actually read the study? I have.

That was the study that found that the users of daytime running lights
had fewer crashes of ALL types, including those types of crashes where
DRLs should have made no difference whatsoever. In fact, DRL users even
had far fewer solo falls off their bikes!

We've mentioned this already. It's very much analogous to the
pro-helmet paper that claimed 85% reduction in head injuries among
helmet wearers, but which hid the fact that their data also showed a 75%
reduction in leg injuries among helmet wearers.

In both cases, it seems obvious that the bulk of the purported benefit
was due to changes in cyclist behavior, not due to the actual
"protective" device.

--
- Frank Krygowski

Okay, these are positive, beneficial psychosomatic effects. I'll take them. Anything that reduces injuries to cyclists is good.

https://www.youtube.com/watch?v=lDWNPL8a_6c
If your bike doesn't have a six foot tall flag made of lights, you're
not safe enough.

Even if you've already installed _all_ of these:
http://tinyurl.com/safe-as-can-be


--
- Frank Krygowski

That red-white-and blue light (5th row down on that page)is illegal in Ontario, Canada if that light flashes.

Cheers

On 7/11/2015 4:09 PM, Frank Krygowski wrote:
On 7/11/2015 4:26 PM, Andre Jute wrote:
On Saturday, July 11, 2015 at 4:30:24 PM UTC+1, Frank
Krygowski wrote:


Have you actually read the study? I have.

That was the study that found that the users of daytime
running lights
had fewer crashes of ALL types, including those types of
crashes where
DRLs should have made no difference whatsoever. In fact,
DRL users even
had far fewer solo falls off their bikes!

We've mentioned this already. It's very much analogous
to the
pro-helmet paper that claimed 85% reduction in head
injuries among
helmet wearers, but which hid the fact that their data
also showed a 75%
reduction in leg injuries among helmet wearers.

In both cases, it seems obvious that the bulk of the
purported benefit
was due to changes in cyclist behavior, not due to the
actual
"protective" device.

--
- Frank Krygowski

Okay, these are positive, beneficial psychosomatic
effects. I'll take them. Anything that reduces injuries to
cyclists is good.

https://www.youtube.com/watch?v=lDWNPL8a_6c
If your bike doesn't have a six foot tall flag made of
lights, you're not safe enough.

Even if you've already installed _all_ of these:
http://tinyurl.com/safe-as-can-be



Gene? Is that you with another Gurgle search link?

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Saturday, July 11, 2015 at 10:09:14 PM UTC+1, Frank Krygowski wrote:
On 7/11/2015 4:26 PM, Andre Jute wrote:
On Saturday, July 11, 2015 at 4:30:24 PM UTC+1, Frank Krygowski wrote:


Have you actually read the study? I have.

That was the study that found that the users of daytime running lights
had fewer crashes of ALL types, including those types of crashes where
DRLs should have made no difference whatsoever. In fact, DRL users even
had far fewer solo falls off their bikes!

We've mentioned this already. It's very much analogous to the
pro-helmet paper that claimed 85% reduction in head injuries among
helmet wearers, but which hid the fact that their data also showed a 75%
reduction in leg injuries among helmet wearers.

In both cases, it seems obvious that the bulk of the purported benefit
was due to changes in cyclist behavior, not due to the actual
"protective" device.

--
- Frank Krygowski

Okay, these are positive, beneficial psychosomatic effects. I'll take them. Anything that reduces injuries to cyclists is good.

https://www.youtube.com/watch?v=lDWNPL8a_6c
If your bike doesn't have a six foot tall flag made of lights, you're
not safe enough.

Even if you've already installed _all_ of these:
http://tinyurl.com/safe-as-can-be


--
- Frank Krygowski

You're right, Franki-boy. I knew you'd see the light some day.

Andre Jute

rOn Sat, 11 Jul 2015 07:57:40 -0700, sms
wrote:

I know how some people dislike any statements that are based on actual
data, but the data is pretty clear.

There is one case-controlled study on bicycle DRLs.

From OECD, International Transport Forum (2013), Cycling, Health and
Safety
https://books.google.com.au/books?id=LvthAgAAQBAJ&pg=PA168&hl=en#v=onepage&q&f =false:
"The safety effect of daytime running lights on bicycles was tested in a
Danish study in 2005 (Madsen 2006). Nearly 2,000 cyclists in the town of
Odense used the new induction lights (?ashing type) for one year with,
while 2,000 others continued with ordinary bike lights, which were only
switched on during dark hours. The accident frequencies of the two
groups (based on self-reported accidents) were then compared and analysed.

The main result was that use of daytime running lights was associated
with a reduction of the number of crashes by more than 30%. The number
of related crashes (crashes in daylight and with a counterpart)
decreased by 50% approximately. Both results are statistically
signi?cant. There are indications that the study may have not controlled
for all factors - for instance it is unclear to what extent the control
group’s crashes included single vehicle crashes (this type of crash is
hardly in?uenced use of induction lights). Also, the study makes no
?nding as to the safety effect of ?ashing versus steady lights."

As you can see, the data on bicycle DRLs is actually much more
compelling than the data on vehicle DRLs! And they weren't creating
bogus studies or intentionally misinterpreting data as one organization
we know of is so fond of doing!

But the reduction in crashes is not the only benefit of DRLs. The other
benefit is how bicycle DRLs shape driver behavior by making cyclists
much more conspicuous in the daytime.

Strange data. On one hand you say that "nearly 2,000 riders..." and
compare that with "while 2000 others". Based on your statement it
wasn't really comparing apples to apples. Another point is that the
number of crashes with or without a consenting partner is going to be
rather low for a mere 2,000 riders on one hand and nearly 2,000 on the
other.

In U.S. terms there is one bicycle death for every 20,000 cyclists in
one year (depending on where you get your numbers from) so your
example study would not have had a really bad crash for what? 5 years?
How long did your study last? I would assume that it must have lasted
for ten years or more to provide accurate results.
--
cheers,

John B.

On 7/11/2015 5:25 PM, John B. Slocomb wrote:
rOn Sat, 11 Jul 2015 07:57:40 -0700, sms
wrote:

I know how some people dislike any statements that are based on actual
data, but the data is pretty clear.

There is one case-controlled study on bicycle DRLs.

From OECD, International Transport Forum (2013), Cycling, Health and
Safety
https://books.google.com.au/books?id=LvthAgAAQBAJ&pg=PA168&hl=en#v=onepage&q&f =false:
"The safety effect of daytime running lights on bicycles was tested in a
Danish study in 2005 (Madsen 2006). Nearly 2,000 cyclists in the town of
Odense used the new induction lights (?ashing type) for one year with,
while 2,000 others continued with ordinary bike lights, which were only
switched on during dark hours. The accident frequencies of the two
groups (based on self-reported accidents) were then compared and analysed.

The main result was that use of daytime running lights was associated
with a reduction of the number of crashes by more than 30%. The number
of related crashes (crashes in daylight and with a counterpart)
decreased by 50% approximately. Both results are statistically
signi?cant. There are indications that the study may have not controlled
for all factors - for instance it is unclear to what extent the control
group’s crashes included single vehicle crashes (this type of crash is
hardly in?uenced use of induction lights). Also, the study makes no
?nding as to the safety effect of ?ashing versus steady lights."

As you can see, the data on bicycle DRLs is actually much more
compelling than the data on vehicle DRLs! And they weren't creating
bogus studies or intentionally misinterpreting data as one organization
we know of is so fond of doing!

But the reduction in crashes is not the only benefit of DRLs. The other
benefit is how bicycle DRLs shape driver behavior by making cyclists
much more conspicuous in the daytime.

Strange data. On one hand you say that "nearly 2,000 riders..." and
compare that with "while 2000 others". Based on your statement it
wasn't really comparing apples to apples.

That was a direct quote from the article, it wasn't "my statement." But
are you really basing your position on the fact that "nearly 2000" does
not exactly equal "2000 others." The results were so overwhelming that
such a slight difference is immaterial.

I'm sure our friend from Ohio doesn't like the fact that this study
proved the effectiveness of DRLs for bicycles but it'd be very difficult
for anyone to dispute the results of this study.

The bottom line is that flashing DRLs work, and _no_ study has
contradicted this one after ten years.

The reason that all the light manufacturers have added flash mode to
lights may be related to this ten year old study. And while I'm certain
that some people will be demanding that more studies need to be
performed the fact is that you're just not going to see anyone spending
money on studies trying to disprove something that everyone knows is
true. Frank is like the 3% of scientists that claim to not believe in
climate change, and even those 3% don't actually believe what they are
saying, they say it because their handlers demand that they say it.

On Saturday, July 11, 2015 at 9:49:54 PM UTC-4, sms wrote:
On 7/11/2015 5:25 PM, John B. Slocomb wrote:
rOn Sat, 11 Jul 2015 07:57:40 -0700, sms
wrote:

I know how some people dislike any statements that are based on actual
data, but the data is pretty clear.

There is one case-controlled study on bicycle DRLs.

From OECD, International Transport Forum (2013), Cycling, Health and
Safety
https://books.google.com.au/books?id=LvthAgAAQBAJ&pg=PA168&hl=en#v=onepage&q&f =false:
"The safety effect of daytime running lights on bicycles was tested in a
Danish study in 2005 (Madsen 2006). Nearly 2,000 cyclists in the town of
Odense used the new induction lights (?ashing type) for one year with,
while 2,000 others continued with ordinary bike lights, which were only
switched on during dark hours. The accident frequencies of the two
groups (based on self-reported accidents) were then compared and analysed.

The main result was that use of daytime running lights was associated
with a reduction of the number of crashes by more than 30%. The number
of related crashes (crashes in daylight and with a counterpart)
decreased by 50% approximately. Both results are statistically
signi?cant. There are indications that the study may have not controlled
for all factors - for instance it is unclear to what extent the control
group's crashes included single vehicle crashes (this type of crash is
hardly in?uenced use of induction lights). Also, the study makes no
?nding as to the safety effect of ?ashing versus steady lights."

As you can see, the data on bicycle DRLs is actually much more
compelling than the data on vehicle DRLs! And they weren't creating
bogus studies or intentionally misinterpreting data as one organization
we know of is so fond of doing!

But the reduction in crashes is not the only benefit of DRLs. The other
benefit is how bicycle DRLs shape driver behavior by making cyclists
much more conspicuous in the daytime.

Strange data. On one hand you say that "nearly 2,000 riders..." and
compare that with "while 2000 others". Based on your statement it
wasn't really comparing apples to apples.

That was a direct quote from the article, it wasn't "my statement." But
are you really basing your position on the fact that "nearly 2000" does
not exactly equal "2000 others." The results were so overwhelming that
such a slight difference is immaterial.

I'm sure our friend from Ohio doesn't like the fact that this study
proved the effectiveness of DRLs for bicycles but it'd be very difficult
for anyone to dispute the results of this study.

The bottom line is that flashing DRLs work, and _no_ study has
contradicted this one after ten years.

The reason that all the light manufacturers have added flash mode to
lights may be related to this ten year old study. And while I'm certain
that some people will be demanding that more studies need to be
performed the fact is that you're just not going to see anyone spending
money on studies trying to disprove something that everyone knows is
true. Frank is like the 3% of scientists that claim to not believe in
climate change, and even those 3% don't actually believe what they are
saying, they say it because their handlers demand that they say it.

If people were transporting tthe bull**** tthat you post about lights in general and the NOT needed DRLs, they'd need 250 ton mining dump trucks to even make a dent in it.

MILIONS, of people ride safely each and every day without using DRLs. It's been pointed out to you why your "2000" study is worthless.

Again, what's your agenda here? To make everyday bicycling sound so dangerous that no one will dare to ride? SHEESH!

Cheers