[geckoGT]

Thanks for some very thought provoking stats and an excellent write up Russ. If only some of the other more vocal members regarding road safety would put as much work in I am sure the quality of these sort of threads would improve.

I have many ideas on the questions you have raised regarding the the disparity of the reduction in overall crash numbers and fatalities compared to the lack of reduction in serious injury crashes. Unfortunately I am in between night shifts at the moment so I should really be sleeping and therefore do not have time to crunch the numbers just yet. I will however throw my thoughts on the table based on my anecdotal experience and give you something to think about and see where my head is at on this subject.

Firstly there is the subject of the reduction of crashes in the urban environment which seems quite good but the seemingly poor reduction in crash numbers in the rural environment. I think this is from a number of factors including better crash avoidance systems on cars, better road design, the introduction of speed cameras and better driver training. The simple fact is that we are having less crashes per road user or per km driven. As much as I hate to say it, the stats seem to show a reduction in the number of crashes across most crash types since the introduction of speed cameras in Vic in 1989, with the largest reduction over the fist 3 years. After that first three years the improvement seems to have plateaued and then in many crash types if began to increase again. So in terms of raw figures speed cameras do appear to be responsible for a reduction in the number of crashes, but do they save lives? That is a more problematic question and one that requires more research and analysis before any reliable conclusion can be made.

I think one of the elements that affects that question is when you look at the urban/rural crash numbers. We all know that speed cameras and other forms of law enforcement devices are many times more prevalent in urban environments. At the introduction of speed cameras in 1989 and over the next few years there was a reduction in crashes in the urban environment by approximately 60%, an outstanding result. It is difficult to pin that all on law enforcement but for the sake of discussion lets just assume increased law enforcement was the largest contributor to that result. However the reduction of crashes in the rural environment was only about 25%, much less than the urban environment. We all know there is no doubt that the focus of improved law enforcement is concentrated in the urban environment, a situation that seems to be confirmed by the improvement in crash numbers for each environment. A statement that I have heard and read many times is that the majority of fatal and severe injury crashes occur in the rural environment and on open highways, a statement I will attempt to get evidence of. Are we putting the law enforcement efforts in the wrong environment from a road safety perspective?

So, if we have seen such a good reduction in the number of crashes, particularly in the urban environment, what has happened to the fatality, serious injury and minor injury figures, surely they should have gone down by an equivalent margin?

The short answer to this is no they have not. The fatality rate dropped fairly consistently over the entire period of the figures shown and this is evidenced by the increase in the number of crashes per fatality graph. There seems to be no obvious reason for the multiple periods of improvement shown on that graph and the 1989 period was no more spectacular than the 1991 or 1993 periods. When I have more time I will attempt to see what else was done in those time periods that may give reason for those improvements. Interestingly the was 2 time periods of a significant in decrease in the number of crashes per fatality in 2001 and 2006, what happened those years?

Now when we compare this to the serious injury chart some surprises are apparent but a little thought sheds some light on the reasons why. We have established there has been a gradual increase in the number of crashes per fatality (positive result), but the number of serious injury crashes seems to be increasing as shown by the crashes per serious injury figure. Surely this is not right and a reduction of fatalities must also result in a reduction in the number of serious injuries. This may be a good time to define serious injury, I am not sure what definition the supplied figures used but a common one I have seen used is any injury that requires hospitalisation for more than 3 days. The raw figures show that the density of serious injury crashes has improved reasonably steadily in the 1988-1997 time period, I would suggest this is due to that significant reduction in overall crash numbers over the same time period. Then in 1997 this figure went down hill fast equalling the 1988 figure in 2001 and by 2007 it was nearly 180% worse than the best figure in 1997 and 65% worse than the starting 1988 figure. I am going to go out on a limb a suggest that the single biggest factor in this result is the introduction of devices such a airbags, seat belt pretensioners, improved structural protection etc.

So is this a bad result for road safety efforts? No not at all, in fact if you overlay the two graphs you would get an interesting result. The time period of the largest improvements for the crashes per fatality figure appears to be around 2003, yet in the same time period the crashes per serious injury worsened considerably. Believe it or not that suggests to me that result is actually an improvement, those that previously would have died are now living, albeit very banged up. I have to wonder if airbags and seat belt pre-tensioners became a lot more widespread in 2003? I know in my observation since 2004, car crashes that we would have peeled a body out of in 2004, we are taking an injured person to hospital in 2011.

As I said I wll try and get some figures later when I have time to do some research. For now I need to get some sleep.

My parting question is, what reduction in the average speed of crashes involving serious injury or fatality has occurred in that same 2003-2011 time period that we saw the reduction in fatality but increase in serious injury numbers? I think that would be a very interesting question to answer in terms of current road safety efforts.