Road collision investigation project: Development of taxonomies and meta-analysis29 Jun 2022

The aim of this report by Neville A Stanton, Professor Emeritus of Human Factors Engineering in the Transportation Research Group at the University of Southampton, is to present the development of taxonomies (classification schemes) for Actor Maps (identification of the main actors contributing to a collision) and AcciMaps (the main events, decisions and actions (or lack thereof) contributing to a collision), as well as the subsequent meta-analyses, as part of the Road Collision Investigation Project (RCIP), which is being led by the RAC Foundation.

On the basis of the study reported here, it is recommended that future effort and resources should be focused on:

1. training road safety investigators in the sociotechnical systems approach using the Actor Map and AcciMap frameworks;
2. undertaking continuous adherence training to ensure that road safety investigators are using the methods appropriately;
3. undertaking a national roll-out of Actor Map and AcciMap frameworks, together with the taxonomies for road safety investigations;
4. prioritising road safety investigations so as to maximise the benefits from the available resources (for example by focusing on: major incidents, indicative incidents that occur frequently, incidents that involve vulnerable road users, incidents involving new technologies such as electric/automated vehicles, and so on);
5. developing a national sociotechnical road safety plan from meta-analysis of Actor Map and AcciMap road safety investigations that increase the protective factors and reduce the contributory factors;
6. continuing to develop and refine the Actor Map and AcciMap taxonomies; and
7. gathering evidence to support the effectiveness of the road safety interventions from the national sociotechnical road safety plan.