Has a test been done to assertain the effectiveness of helmets?

[Red Light]

I don't know which states he was referring to, but here are a couple of candidates.

Exactly, significant drops in both cases before the helmet laws came in and in groups that were not affected by the helmet law. Victoria introduced its helmet law on 1 July 1990 as indicated on the above graph but South Australia's wasn't introduced until 1 July 1991 and Western Australia's not until 1 Jan 1992 so can't have been influenced by Cunobelin's active safety campaign in 1989/90.

 

[ufkacbln]

Which Australian state are you referring to? The law was introduced in different years in different states.

Victoria, both the speeding campaign and helmet compulsion were introduced in 1990, and it is alo the state where head injuries decreased, but so did the number of cyclists. The problem being that when corrected for the fall in cyclist numbers the head injury rate was higher for thise cycling than before compulsion

 

[Red Light]

Victoria, both the speeding campaign and helmet compulsion were introduced in 1990, and it is alo the state where head injuries decreased, but so did the number of cyclists. The problem being that when corrected for the fall in cyclist numbers the head injury rate was higher for thise cycling than before compulsion

But what about all the other states? Taking one in isolation might give confounded results but looking at them as a collection rules out most factors as does taking a simple injury ratio for cyclist head injuries in Victoria.

 

[ufkacbln]

It comes as a package....

We have the accident figures for Victoria, and the details of what happened in Victoria.

The graph you show is in itself biased as it does not correct for the reduction in the number of cyclists.

Depending on the source, the number of cyclists in Victoria declined by between 25% and 35%, a reduction NOT reflected in this graph or the figures for head injury admissions!

Now look at the claimed helmet wearing rate. This increased from 31% to 75 %, if helmets were that effective we should then (in really rough terms) expect that doubling helmet use should halve the head injury rate

The decrease is again not reflecting this

 

[Red Light]

It comes as a package....

We have the accident figures for Victoria, and the details of what happened in Victoria.

The graph you show is in itself biased as it does not correct for the reduction in the number of cyclists.

Depending on the source, the number of cyclists in Victoria declined by between 25% and 35%, a reduction NOT reflected in this graph or the figures for head injury admissions!

Now look at the claimed helmet wearing rate. This increased from 31% to 75 %, if helmets were that effective we should then (in really rough terms) expect that doubling helmet use should halve the head injury rate

The decrease is again not reflecting this

It does correct for the drop in cyclists because it compares the number of head injuries with the number of cyclist injuries. What it shows is that a more than doubling of helmet wearing resulted in no change in the proportion of accidents that resulted in head injuries. The "other injuries" does the normalising for you because if the accident rate drops due to fewer people cycling or less cars on the road or an anti-speeding campaign that is automatically factored in to normalise the result. I think though we are both arguing for the same conclusion - there is no evidence that helmets have had any effect on the risk of head injuries.

 

[Nantmor]

I think though we are both arguing for the same conclusion - there is no evidence that helmets have had any effect on the risk of head injuries.

I've been puzzled by your exchange too. I thought you were both arguing for the same conclusion.

 

[ufkacbln]

It does correct for the drop in cyclists because it compares the number of head injuries with the number of cyclist injuries. What it shows is that a more than doubling of helmet wearing resulted in no change in the proportion of accidents that resulted in head injuries. The "other injuries" does the normalising for you because if the accident rate drops due to fewer people cycling or less cars on the road or an anti-speeding campaign that is automatically factored in to normalise the result. I think though we are both arguing for the same conclusion - there is no evidence that helmets have had any effect on the risk of head injuries.

I agree, it is simply how the data is interpreted.

 

[classic33]

http://www.rcsed.ac.uk/journal/vol44_2/4420027.htm

 

[classic33]

http://www.rcsed.ac.uk/journal/vol44_2/4420027.htm