Experimental Model

Factors affecting Road Fatalities

What factors affect road fatalities in the UK, and how are they changing?


We see road safety in the UK as a huge system with plenty of inertia. Various inputs take place including for example increases in traffic volumes and improvements in vehicle safety. All the inputs together cause a series of outputs or results, including for example the number of fatal accidents.

We've long been interested in exploring what the inputs are, and how they are changing.

Accordingly we've devised an experimental model based on a spreadsheet that allows inputs to be adjusted and allows the outputs to be compared with real data.

Early results are encouraging in that it proved quite easy to achieve credible outputs.

The first remarkable finding is that it is necessary of one (or more) of the inputs to change for the worse by an annual factor of about  6% in 1993 to get a credible fit to modern reality.

This is an ongoing experiment, and we hope to be able to progressively revise and improve the model over time to account for real and known alterations in the UK road safety system. 

On this basis we invite suggestions, links to research, further analysis, revisions to the spreadsheet etc. from any source. Just use the forum based comments facility (below) or send us email. (click here)

Fatality Graph from version 0.5 of the experimental model


The latest Excel 97 spreadsheet (click here)

Version history
Release Date Notes
Version 0.5 21st September 2003 Initial Release
Reference material

A study from Loughborough University regarding improvements in vehicle crash performance over the 1990s:


(click here)

We are investigating - but they report that late 90s cars are 24% safer in crashes than early 90s cars.

new Comments

Safe Speed encourages comments, further information and participation from our visitors. See our (forums).

Read about our comments policy (here).

Many pages (including this one) have a specific associated forum topic. You can (view) or (add comment) to the forum topic for this page. Posting in the forum requires simple registration.

Promoting intelligent road safety

We have a strict editorial policy regarding factual content. If any fact anywhere on this web site can be shown to be incorrect we promise to remove it or correct it as soon as possible.
Copyright © SafeSpeed 2003, 2004
Created 21/09/2003. Last update 7/03/2004