Academy school makes cycle helmets compulsory and says it will suspend pupils who ride on the pavement

CygnusX1 wrote:

@Rich_cb

We're going to have to agree to disagree on whether helmets save lives once an accident occurs, life is too short for yet another helmet debate.

Would you agree that

1) A helmet is 'treatment' for the symptom (busted skull), not the cause (road traffic collision)?

2) Pavement cycling on the way to this school is also a symptom, whereas the cause is (a) cars blocking the cycle lanes, (b) fear/risk of a child on a bike being involved in an RTC if they cycled on the road?

The headteacher needs to focus on treating the cause not the symptoms.  Or at least stop meddling in areas that are not his remit.

Indeed, so let's keep it to personal choice. The Netherlands has the lowest rate of cycling deaths due to head injury and very few Cyclists wear helmets there, it's down to  better driving attitudes by drivers

Moreu live could be saved by improving passing distances, and introducing presumed liability.

It's a sad state of affairs when schools are introducing these rules, as when I was a lad, loads of us cycled to school and there was big bike sheds. No one got lifts to school.

At my daughter's academy, quite a few kids cycle to school, most of them quite sensibly, at lot ride on the pavement, but it's quite a busy road. I'd be in favour of some sort of training to educate them about this and other road craft, rather than impose rules that discourage cycling to school.

maviczap wrote:

It's a sad state of affairs when schools are introducing these rules, as when I was a lad, loads of us cycled to school and there was big bike sheds. No one got lifts to school.

At my daughter's academy, quite a few kids cycle to school, most of them quite sensibly, at lot ride on the pavement, but it's quite a busy road. I'd be in favour of some sort of training to educate them about this and other road craft, rather than impose rules that discourage cycling to school.

Especially when there is no legal requirement and another example of a head exceeding their powers and being totally inconsistent in applying alleged health and safety.

CygnusX1 wrote:

@Rich_cb

We're going to have to agree to disagree on whether helmets save lives once an accident occurs, life is too short for yet another helmet debate.

Would you agree that

1) A helmet is 'treatment' for the symptom (busted skull), not the cause (road traffic collision)?

2) Pavement cycling on the way to this school is also a symptom, whereas the cause is (a) cars blocking the cycle lanes, (b) fear/risk of a child on a bike being involved in an RTC if they cycled on the road?

The headteacher needs to focus on treating the cause not the symptoms.  Or at least stop meddling in areas that are not his remit.

Yes we can agree on all those points.

I would love to see headteachers concentrating on curbing the huge amounts of dangerous driving and parking that accompany the school run everyday rather than harassing the small number of pupils not contributing to pollution/congestion/obesity.

Kendo wrote:

Nice response from Cycling UK to that story. I hope they've sent the same to the Head direct.

+1.

"instead of applying his efforts to make it easier and safer for children to cycle to school, the headteacher has threatened to ban children from cycling to school"

What a complete and utter knob! And he's in charge of a secondary school?!?    I wouldn't trust him to operate a fountain pen properly.

Tommytrucker wrote:

I wonder what Mr Gray's position would be if the unthinkable happened, and a child who previously rode slowly and carefully along the pavement to school as they weren't confident in riding on the road, was involved in a collision with a car because he / she was following the demands of the school?

Well, the kid would be less likely to be cycling to school, anyway - and this is the crux, for me (I pull rich_cb's yarn about those graphs, but I know there are studies and metastudies that show helmets prevent certain types of injury. I also know that when you throw in risk compensation/offsetting behaviour and cycling rates, the overall picture is very quickly muddied).

The 'unintended consequences' with mandated helmet use in NZ and Australia are so well-documented that they surely fall out of the realm of 'unintended consequences'. They are well known. They are easily found via Google. They're written about in the MSM. If you mandate helmets, you might save some lives, but how many, and how, will be the subject of debate. But you sure as shit WILL significantly decrease cycling, with an imperial fuckton of other unintended consequences.

This is a clearer correlation than any injury reduction. So forget Gray's weasel words and let's give him the credit he probably thinks he deserves as a headteacher. He has set out to reduce cycling rates by 30-50%. I predict he'll be successful.

Rich_cb wrote:

Oh really?

Yes, really. Your own graphs support it. Despite the increase in helmet usage in graph one, the rate of injury has remained in line with that of pedestrians (graph 2) who are pretty much 100% non-helmet wearers. Therefore helmet use has had no impact on casualties.

CygnusX1 wrote:

Rich_cb wrote:

Oh really?

Yes, really. Your own graphs support it. Despite the increase in helmet usage in graph one, the rate of injury has remained in line with that of pedestrians (graph 2) who are pretty much 100% non-helmet wearers. Therefore helmet use has had no impact on casualties.

Actually, over the same time frame as the helmet increase graph (1st graph), ped deaths per km have fallen more than cyclists (2nd graph).

So, purely from those two graphs, the only rational conclusion one can make is that pedestrians, with zero helmet use, saw a significantly larger fall (about twice the decrease as cyclists from 1994-2008) in deaths than cyclists, although cyclist helmet use doubled during that time.

Whatever those graphs are, they're not an argument for the efficacy of helmets in death prevention, and if the argument is using peds as a control, you're more likely to conclude that you're safer NOT wearing a helmet.

TL;DR: apparently, doubling helmet use results in halving the decrease in death rates.

davel wrote:

Actually, over the same time frame as the helmet increase graph (1st graph), ped deaths per km have fallen more than cyclists (2nd graph).

So, purely from those two graphs, the only rational conclusion one can make is that pedestrians, with zero helmet use, saw a significantly larger fall (about twice the decrease as cyclists from 1994-2008) in deaths than cyclists, although cyclist helmet use doubled during that time.

Whatever those graphs are, they're not an argument for the efficacy of helmets in death prevention, and if the argument is using peds as a control, you're more likely to conclude that you're safer NOT wearing a helmet.

TL;DR: apparently, doubling helmet use results in halving the decrease in death rates.

You've failed to interpret the graphs properly.

The cyclist rate doesn't start falling significantly until 1995.

It falls faster than the pedestrian rate for the next 10 years.

That accelerated fall correlates exactly with the increased use of helmets thus completely disproving the original point I was replying to.

davel wrote:

 The cyclist rate doesn't start falling significantly until 1995. 

I would argue the cyclist rate doesn't have a statistically significant change until 2000, when by eyeball I think there may be the start of 3 points on the same side of the mean by more than 2 standard deviations, and it stays that way. 

Any correlations are weak, and just on this data set it would be unwise to infer causality. 

Doesn't mean helmets aren't useful, just this is not evidence of their usefulness.

A cautionary correlation tale: For example, there is a strong correlation between per capita cheese consumption, and death by beadsheet entanglement. I hypothesise this is because cheese causes strange dreams, hence writhing in sleep, hence deaths. We should campaign for the school to ban children from pizza in the afternoon. 

Data source

http://www.tylervigen.com/spurious-correlations

Drinfinity wrote:

davel wrote:

 The cyclist rate doesn't start falling significantly until 1995. 

I would argue the cyclist rate doesn't have a statistically significant change until 2000, when by eyeball I think there may be the start of 3 points on the same side of the mean by more than 2 standard deviations, and it stays that way. 

Any correlations are weak, and just on this data set it would be unwise to infer causality. 

Doesn't mean helmets aren't useful, just this is not evidence of their usefulness.

My minitab days are long behind me, and I don't think I've ever been able to reliably eyeball deviations from graphs, hence my wordy post 

(I think quotes have got messed up and it was rich_cb wot said that, not me)

Amen to all that though.

Rich_cb wrote:

You've failed to interpret the graphs properly. The cyclist rate doesn't start falling significantly until 1995. It falls faster than the pedestrian rate for the next 10 years. That accelerated fall correlates exactly with the increased use of helmets thus completely disproving the original point I was replying to.

We're interpreting it differently... I think it's your bias that's making you think your view is correct.

By examining the statements you make that can be measured, I think we can decide that you're interpreting it (or, just reading it) incorrectly.

The cyclist rate doesn't start falling significantly until 1995.

Not true: between 1989 and 1992 over 10 fatalities per billion km are scrubbed off. There is a  downward and sustained trend that you refer to after 1995, for the next decade. However, that is more than matched by the ped rate decrease. Which brings us to...

It falls faster than the pedestrian rate for the next 10 years.

No it doesn't.

Cyclists

1995: 52

2005: 34

or 35%

Peds

1995: 56

2005: 36

or 36%

In fact - take cycling's biggest dip, over the shortest timeframe: 95-03, a fall from 52 to 26ish, about 26 (50%) over 8 years - or halving. In the same timeframe, peds go from 56 to 35, a fall of about 21 (38%). ONLY if you focus on that spell do you fit your argument - and even then there's only a 12% difference, which is nullified by the next few years.

But Peds fall from 75 in 1992 to 36 in 2004... More than halving, a decrease of 39 (52%) in 12 years. There is no absolute fall like that on the cyclist side, and proportionally, ped deaths also halve over the same decade. 

It is safe, and correct, to say that from the early-mid 90s, over the next decade, cyclist and pedestrian death rates halved. Your interpretation of your second graph stems from your desire for it match your first graph - ie., to explain the cycling fall via helmets.

Roads got safer for peds and cyclists in that period: by the end of both graphs' scales, around two thirds of cyclists, and 100% of pedestrians, were not wearing helmets. Inferring a measurable impact from helmet-wearing just cannot be done from these graphs.

davel wrote:

We're interpreting it differently... I think it's your bias that's making you think your view is correct.

By examining the statements you make that can be measured, I think we can decide that you're interpreting it (or, just reading it) incorrectly.

The cyclist rate doesn't start falling significantly until 1995.

Not true: between 1989 and 1992 over 10 fatalities per billion km are scrubbed off. There is a  downward and sustained trend that you refer to after 1995, for the next decade. However, that is more than matched by the ped rate decrease. Which brings us to...

It falls faster than the pedestrian rate for the next 10 years.

No it doesn't.

Cyclists

1995: 52

2005: 34

or 35%

Peds

1995: 56

2005: 36

or 36%

In fact - take cycling's biggest dip, over the shortest timeframe: 95-03, a fall from 52 to 26ish, about 26 (50%) over 8 years - or halving. In the same timeframe, peds go from 56 to 35, a fall of about 21 (38%). ONLY if you focus on that spell do you fit your argument - and even then there's only a 12% difference, which is nullified by the next few years.

But Peds fall from 75 in 1992 to 36 in 2004... More than halving, a decrease of 39 (52%) in 12 years. There is no absolute fall like that on the cyclist side, and proportionally, ped deaths also halve over the same decade. 

It is safe, and correct, to say that from the early-mid 90s, over the next decade, cyclist and pedestrian death rates halved. Your interpretation of your second graph stems from your desire for it match your first graph - ie., to explain the cycling fall via helmets.

Roads got safer for peds and cyclists in that period: by the end of both graphs' scales, around two thirds of cyclists, and 100% of pedestrians, were not wearing helmets. Inferring a measurable impact from helmet-wearing just cannot be done from these graphs.

The rate pre 1995 is just showing normal variation. If you look at the trend for cyclists it's basically static despite a significant fall in the pedestrian rate over the same period.

1989-92 is just part of the normal fluctuations.

Post 1995 the fall is sustained.

The fall in cyclist fatality rate correlates almost exactly with the increase in helmet use.

Thus disproving the original point.

Rich_cb][quote=davel wrote:

The rate pre 1995 is just showing normal variation. If you look at the trend for cyclists it's basically static despite a significant fall in the pedestrian rate over the same period. 1989-92 is just part of the normal fluctuations. Post 1995 the fall is sustained. The fall in cyclist fatality rate correlates almost exactly with the increase in helmet use. Thus disproving the original point.

And as any fule gnows, correlation is not causation.  Drowning correlates with ice cream consumption, so do they cause drowning?

Are you claiming that helmets are entirely responsible for the decline in deaths and that no other factor was involved?  If so, how do you explain the fall in pedestrian deaths?

burtthebike wrote:

And as any fule gnows, correlation is not causation.  Drowning correlates with ice cream consumption, so do they cause drowning?

Are you claiming that helmets are entirely responsible for the decline in deaths and that no other factor was involved?  If so, how do you explain the fall in pedestrian deaths?

The original point was that cycling deaths did not fall after an increase in helmet use. That point is proved wrong by the graph.

You can't prove causation but you can say that the graphs strongly suggest a cyclist specific factor becoming significant post 1995.

Prior to that the pedestrian rate had already fallen markedly with no significant change in the cyclist rate. That suggests a pedestrian specific factor, would that factor disappear in 1995 or continue to exert an effect?

If we're looking for a cyclist specific factor that becomes significant post 1995 then helmet use fits.

It doesn't prove causation but I don't know of any other cycling specific factors that fit the timescale?

Rich_cb wrote:

davel wrote:

We're interpreting it differently... I think it's your bias that's making you think your view is correct.

By examining the statements you make that can be measured, I think we can decide that you're interpreting it (or, just reading it) incorrectly.

The cyclist rate doesn't start falling significantly until 1995.

Not true: between 1989 and 1992 over 10 fatalities per billion km are scrubbed off. There is a  downward and sustained trend that you refer to after 1995, for the next decade. However, that is more than matched by the ped rate decrease. Which brings us to...

It falls faster than the pedestrian rate for the next 10 years.

No it doesn't.

Cyclists

1995: 52

2005: 34

or 35%

Peds

1995: 56

2005: 36

or 36%

The rate pre 1995 is just showing normal variation. If you look at the trend for cyclists it's basically static despite a significant fall in the pedestrian rate over the same period. 1989-92 is just part of the normal fluctuations. Post 1995 the fall is sustained. The fall in cyclist fatality rate correlates almost exactly with the increase in helmet use. Thus disproving the original point.

You really are a bit dense (from Davels post): -

                                      Cyclists          Peds

                                     1995: 52          56

                                     2005: 34          36

  Death rate decrease: 35%         36%

THEREFORE decrease in death rate is greater for group NOT wearing helmets. IF helemets made a statistically greater impact (other than general road safety methods) then the death rate decrease (for cyclists) would have to be circa 40%.

Dropped wrote:

You really are a bit dense (from Davels post): -

                                      Cyclists          Peds

                                     1995: 52          56

                                     2005: 34          36

  Death rate decrease: 35%         36%

THEREFORE decrease in death rate is greater for group NOT wearing helmets. IF helemets made a statistically greater impact (other than general road safety methods) then the death rate decrease (for cyclists) would have to be circa 40%.

Let's not start throwing insults around.

Look at the pedestrian rate.

When does it start to decline?

Is there a corresponding fall in the cyclist rate?

If there is no corresponding fall (there isn't) that suggests a factor specific to pedestrians is the cause.

When the cyclist rate begins its decline in 1995 there is no corresponding increase in the rate of decline for pedestrians, this suggests that the new factor is cyclist specific.

Helmets fit that criteria, they are cyclist specific and the time frame fits almost exactly.

You can't prove causation but I can't think of any other cycling specific factors that fit that timescale.

Can you?

Rich_cb wrote:

I can't think of any other cycling specific factors that fit that timescale.

Chris Boardman's career.

Rich_cb wrote:

davel wrote:

Actually, over the same time frame as the helmet increase graph (1st graph), ped deaths per km have fallen more than cyclists (2nd graph). So, purely from those two graphs, the only rational conclusion one can make is that pedestrians, with zero helmet use, saw a significantly larger fall (about twice the decrease as cyclists from 1994-2008) in deaths than cyclists, although cyclist helmet use doubled during that time. Whatever those graphs are, they're not an argument for the efficacy of helmets in death prevention, and if the argument is using peds as a control, you're more likely to conclude that you're safer NOT wearing a helmet. TL;DR: apparently, doubling helmet use results in halving the decrease in death rates.

You've failed to interpret the graphs properly. The cyclist rate doesn't start falling significantly until 1995. It falls faster than the pedestrian rate for the next 10 years. That accelerated fall correlates exactly with the increased use of helmets thus completely disproving the original point I was replying to.

Lies, damn lies and statistics

The two graphs are not comparable as they contain different sets of data.
One has details on changes on helmet rate wearing by % of cyclists
One has reported fatalities of cyclists per billion KM travelled

If you wanted to compare statistics you would need to have:

Statistics on changes on helmet rate wearing by % of cyclists
Statistics on reported fatalities of cyclists by % of cyclists

or

Statistics on changes on helmet rate wearing per billion KM travelled
Statistics on reported fatalities of cyclists per billion KM travelled

Without the above similar data sets to compare no meaningful conclusions can be made as we do not know if hemlet wearers are more or less likely to do longer journeys (or if so by how much or if they wear their helmet at all times on all journeys etc, etc) which would be needed to even begin to get close to being able to draw a conclusion.

ClubSmed wrote:

Lies, damn lies and statistics

The two graphs are not comparable as they contain different sets of data.
One has details on changes on helmet rate wearing by % of cyclists
One has reported fatalities of cyclists per billion KM travelled

If you wanted to compare statistics you would need to have:

Statistics on changes on helmet rate wearing by % of cyclists
Statistics on reported fatalities of cyclists by % of cyclists

or

Statistics on changes on helmet rate wearing per billion KM travelled
Statistics on reported fatalities of cyclists per billion KM travelled

Without the above similar data sets to compare no meaningful conclusions can be made as we do not know if hemlet wearers are more or less likely to do longer journeys (or if so by how much or if they wear their helmet at all times on all journeys etc, etc) which would be needed to even begin to get close to being able to draw a conclusion.

You can't prove causation but I didn't say you could.

You can say that the data suggests a cycling specific factor post 1995 and that increased helmet use is a cyclist specific factor that changed significantly over the same period.

Rich_cb wrote:

ClubSmed wrote:

Lies, damn lies and statistics

The two graphs are not comparable as they contain different sets of data.
One has details on changes on helmet rate wearing by % of cyclists
One has reported fatalities of cyclists per billion KM travelled

If you wanted to compare statistics you would need to have:

Statistics on changes on helmet rate wearing by % of cyclists
Statistics on reported fatalities of cyclists by % of cyclists

or

Statistics on changes on helmet rate wearing per billion KM travelled
Statistics on reported fatalities of cyclists per billion KM travelled

Without the above similar data sets to compare no meaningful conclusions can be made as we do not know if hemlet wearers are more or less likely to do longer journeys (or if so by how much or if they wear their helmet at all times on all journeys etc, etc) which would be needed to even begin to get close to being able to draw a conclusion.

You can't prove causation but I didn't say you could. You can say that the data suggests a cycling specific factor post 1995 and that increased helmet use is a cyclist specific factor that changed significantly over the same period.

You could say that the data of increased sales of ice-cream at the beach during summer months and the increase of shark attacks during the same period suggests that sharks are attracted to ice-cream. You would be wrong to draw such a conclusion though as the two sets of data are not connected to each other.

ClubSmed wrote:

You could say that the data of increased sales of ice-cream at the beach during summer months and the increase of shark attacks during the same period means that sharks are attracted to ice-cream. You would be a fool to draw such a conclusion though as the two sets of data are not connected to each other.

Correlation isn't always causation but it is sometimes.

There is a clear correlation between increased helmet use and decreasing cyclist deaths.

Do you know of any other correlations that are more likely to be causative?

Rich_cb wrote:

ClubSmed wrote:

You could say that the data of increased sales of ice-cream at the beach during summer months and the increase of shark attacks during the same period means that sharks are attracted to ice-cream. You would be a fool to draw such a conclusion though as the two sets of data are not connected to each other.

Correlation isn't always causation but it is sometimes. There is a clear correlation between increased helmet use and decreasing cyclist deaths. Do you know of any other correlations that are more likely to be causative?

Increase in the number of cyclists resulting in more driver awareness that they exist so more likely to look out for them?

ClubSmed wrote:

Increase in the number of cyclists resulting in more driver awareness that they exist so more likely to look out for them?

I don't think that fits the timeline.