Australian Cycling Forums - Bicycles Network Australia

The recently published paper by Boufous, de Rome, Senserrick, & Ivers (2012) published in Accident Analysis and Prevention takes a look the influence of road and crash characteristics on the injury severity of cyclists involved in traffic crashes and hence adds to our understanding of the injury risks to cyclists.

The abstract of the paper follows:

This study examines the impact of cyclist, road and crash characteristics on the injury severity of cyclists involved in traffic crashes reported to the police in Victoria, Australia between 2004 and 2008. Logistic regression analysis was carried out to identify predictors of severe injury (serious injury and fatality) in cyclist crashes reported to the police. There were 6432 cyclist crashes reported to the police in Victoria between 2004 and 2008 with 2181 (33.9%) resulting in severe injury of the cyclist involved. The multivariate analysis found that factors that increase the risk of severe injury in cyclists involved in traffic crashes were age (50 years and older), not wearing a helmet, riding in the dark on unlit roads, riding on roads zoned 70 km/h or above, on curved sections of the road, in rural locations and being involved in head-on collisions as well as off path crashes, which include losing control of vehicle, and on path crashes which include striking the door of a parked vehicle. While this study did not test effectiveness of preventative measures, policy makers should consider implementation of programs that address these risk factors including helmet programs and environmental modifications such as speed reduction on roads that are frequented by cyclists.

If you are interested in the full paper you can find the download link at my blog.

Andrew

Its not a particularly interesting study I'm afraid, as its one set of very distant public data, combined with a lot of literature review and barfing up of other peoples conclusions.

The helmet conclusions look politicised for the paymasters - ie they are capable of distinguishing that modern cyclists have lights, and that their night injury data doesn't extend to lights usage or quality, but they are not capable of making the similar leap understanding that their data does not contain riding behavior data, and that regardless of mandatory law, there is still choice being applied to helmet usage, and that choice is almost certainly correlated with general risk management of the rider.

Also by not having population data, (including people that don't have accidents), the helmet conclusions also get further out of whack, ie without population data, the 25% or so of non helmet wearers in the stats, could be a very low proportion of the actual riding trip or km population. It could be 15% or 10%, and therefore a lot of expense could be expended on further helmet enforcement and communication that will (a) not affect the target groups helmet behavior much and (b) not change their riding practices in general, where poor practices are likely to be correlated with non helmet use.

Gee, do you think for five second you could NOT turn it into another MHL thread?

Off the top of my head, people not wearing helmets were always over-represented in fatalities/serious injuries given that only a small percentage of cyclists are observed to ride without one. Unless you can show that the number lie, why not just accept that it's indicative that if you choose to ride without a helmet you are statistically more likely to be the subject of one of these studies?

Right - now that's off my chest, let's return to having a holistic view of the report instead of bitching about one aspect of it.

Most of those things sound obvious - faster roads, car doors, curves and bends, riding in the dark, etc, and not to go all MHL on anyone, but helmetless riders are probably comfortable with higher levels of risk generally.

I'm not sure why the over-50s are over-represented though.

Over 50's...hmmm maybe I need to start to worry?

twizzle wrote:Gee, do you think for five second you could NOT turn it into another MHL thread?

It happens to be the most objectively poor part of the study, and the one for which they make the most concrete recommendation for spending money, which happens to align with the stated policies of their funding organisations.

It also ignores an (IMO more valuable because of the fresh data) study of Victorian casualties, which included phone interviews of accident victims, and which happens to demonstrate the headlight effect on accident severity (ie taken as a modeled variable alone, a headlight turned on during broad daylight predicts less severe single vehicle accidents - which cannot be explained by the function of the headlight).

Howzat wrote:I'm not sure why the over-50s are over-represented though.

Over 50s are generally more brittle and have slower reaction times. Even at 44 I'm fracturing much easier than in my 20s.

Nobody wrote:Over 50s are generally more brittle and have slower reaction times. Even at 44 I'm fracturing much easier than in my 20s.

Yeah that might be it. Plus they might have better lawyers. I had my share of prangs when I was a kid, and the police were never called.

Howzat wrote:

Nobody wrote:Over 50s are generally more brittle and have slower reaction times. Even at 44 I'm fracturing much easier than in my 20s.

Yeah that might be it. Plus they might have better lawyers. I had my share of prangs when I was a kid, and the police were never called.

I must admit in looking at Bike Insurance it occured to me that as a 50 year old bloke on a road bike the chance of someone looking at me and thinking money did occur to me, so I choose insurance which includes liability cover. Perhaps you're far more right than you think. If you are involved in an incident with a 17 year old they probably have no money, a 50+ probably has a house etc, etc.

Apart from the blindingly obvious factors like age, barehead and high speed roads I fail to understand how the rest could be deemed to have a higher risk of severe injury. Risk of pranging maybe, but actual injury?

Mulger bill wrote:Apart from the blindingly obvious factors like age, barehead and high speed roads I fail to understand how the rest could be deemed to have a higher risk of severe injury. Risk of pranging maybe, but actual injury?

What they mean, is for reported incidents a greater proportion of them involve serious injuries.

There is no population exposure that tells you either how many kms are done without reported crashes, how many participants, how many trips, or how that is mapped against the proportions of each type of infrastructure.

Nobody wrote:

Howzat wrote:I'm not sure why the over-50s are over-represented though.

Over 50s are generally more brittle and have slower reaction times. Even at 44 I'm fracturing much easier than in my 20s.

Were not likely to ever get stats that include all levels of crashes, but would be good to find out if older riders crash more or just suffer worse injuries. I suspect the latter, over 50s generally take less risks

tubby74 wrote:
Were not likely to ever get stats that include all levels of crashes, but would be good to find out if older riders crash more or just suffer worse injuries. I suspect the latter, over 50s generally take less risks

Not so sure about that.

By the time you get well over 50 your hearing starts to deteriorate, your eye sight worsens considerably, and with far too many the instant decision making process and reaction speed starts to deteriorate.

Less able to avoid danger due to slower reaction times, or not seeing the danger in time and recognising it for what it is?

A quick look at Beach road on Sundays shows the problems of being a 55 year old male cyclist.

I have some difficulty with rotating my head around to the left and holding it there. And the need to hold it a while is born out of my less than perfect vision. Both issues coming on with and advancing with age.