The general objective of the TRACE project is to provide the scientific community, the stakeholders, the suppliers, the vehicle industry and other Integrated Safety program participants with an overview of the road accident causation issues in Europe, and possibly overseas, based on the analysis of any current available databases which include accident, injury, insurance, medical and exposure data (including driver behaviour in normal driving conditions). In accordance with these objectives, TRACE has been divided into 3 series of technical Workpackages:
• The Operational Workpackages (WP1 Road Users – WP2 Types of driving situations and types of accident situations – WP3 Types of risk factors – WP4 Evaluation of the effectiveness of safety functions in terms of expected (or observed) accidents avoided and lives saved). • The Methodologies Workpackages (WP5 Analysis of Human factors – WP7 Statistical
Methods – WP6 Determination of Safety Functions). • The Data Supply Workpackage (WP8).
Related to ‘Operational Workpackage’, ‘Work Package 2: Type of situations’ has been aimed to update accident causation knowledge from the road user situation point of view (stabilized situation, intersection situation, specific manoeuvre and degraded situation).
Firstly, TRACE has proposed a common methodology for the analysis of each type of situation maximizing the use of existing databases and their limitations. This integrated methodology can be summarized as follows:
Question Methodology Delivrable
What knowledge has already been obtained for each road user?
Literature review Deliverable D2.1 What are the most relevant accident
configurations at European level?
Descriptive analysis Deliverable D2.1 Why accidents of those
configurations take place?
In-depth analysis Deliverable D2.2 Which factors increase the risk of
each accident configuration?
Risk analysis Deliverable D2.2
Each task has followed the above method in order to study the different type of situations. The main achievements, apart from the specific results on each task, make reference to the following facts:
• Innovative statistical methods, developed by WP7, have been applied as much as possible in order to provide data at EU27 level related to the magnitude of the accident figures for each type of situation although this was an initial target of the project. When available, these figures have been combined with exposure data in order to provide general risks estimations.
• Relevant & specific accident configurations have been detected and describing for each type of situations at macroscopic level. This means that safety solutions addressing these configurations would benefit to larger groups of road users.
• Contributory factors have been identified through microscopic analysis in order to detect what aspects have contributed to the accident. This is what topics should new safety systems would be addressing. The WP5 methodology to identify Human Functional Failure has been applied in this step allowing the identification of the human decisions mechanisms that did not perform positively in each accident configuration.
• Last but not least, the different risk analyses performed allow deciding which new systems should be prioritized as they address factors that induce a higher level of risk for each road user.
September 2009 - 69 - TRACE differs from other accident research project both on the methodology used and the collating of almost all the relevant accident databases at European level both at macroscopic and microscopic level.
Nevertheless, this does not mean that everything is achieved in accident causation.
This project has also encountered some relevant difficulties that should help the research community to identify the next actions to be taken:
About the data.
• Whether it is for road accident databases so called aggregated (such as CARE) or detailed (in- depth) it is important that a common structure to all the European countries is set up and applied. If descriptive analyses regarding situations have to be made, the information regarding the pre-accidental manoeuvres for each road users involved in the accident have to be included. This implies to take into account the 2 following aspects:
o To add at accident level a pictogram describing the main pre-accidental situation, i.e. the one who led to the accident.
o To identify a road users level with information related to its manoeuvre (overtaking, changing lane, u-turning, turning to the left, turning to the right, go straightforward reversing, etc.).
• There is not enough data to perform all the ideal risk analyses in accident causation. Sometimes there is a lack of data related to the detail on the studied population and sometimes it is not possible to get the necessary exposure data to perform risk (e.g. on driving behaviour, elder driver, etc.).
If a common accident investigation methodology is applied in the future (as proposed by the SafetyNet project), this will allow performing a new updating of the accident causation knowledge under this approach.
The last problem focused on the application of the innovative methodology emerging from WP5 – Analyzing “Human Functional Failure” in road accidents. Two difficulties appeared:
• We need to well understand the new approach if we want to have relevant results and to have the same understanding of the approach between all the partners.
• Once the approach understood, we have to find in our database the appropriated information which could help us to apply the new approach on our sample.
All potential users of the results of this work package should not only consider the different percentages and specific conclusions of each type of situations but also the methodology followed to obtain each result. Both objectives of developing and applying the methodology for the updating and accident causation have been achieved within this work package from the point of view of road users.
September 2009 - 70 -