A Common Approach to Understanding Strengths and Limitations of Different Techniques for Quantifying Casualty Benefits.

Policy makers require evidence of the costs and benefits of a safety measure to inform their views in policy decisions. These analyses are often required in a short period of time with limited research budgets. Increasingly, the measures considered are advanced control systems intended to help drivers to avoid a collision. It is inherently difficult to accurately assess the casualty effects of such systems and this, combined with resource constraints, often results in a wide range of conflicting predictions based on different assumptions, simplifications and analytical techniques. Substantial variation in the presentation of results can make it difficult for researchers to directly compare different studies. In turn, this makes it difficult for policy makers to be confident of the right approach. As a result, studies of very different levels of reliability are often given equal weight in policy debates, risking the possibility of less than optimalimplementation of new safety features. This paper describes the development of a methodology intended to allow a preliminary assessment of the potential benefits of advanced safety systems to be undertaken in a consistentand objective manner. An initial methodology was developed, based on literature and expert opinion, and then tested and refined by applying it to an assessment of existing studies of advanced braking systems for motorcycles. The research was, therefore, limited to a relatively narrow scope. However, the potential for the method to be expanded in future was explored to assess the possibility of providing a generic methodology to provide guidance for policy makers and researchers alike regarding the: scientific confidence required from a new study or implied by existing analyses; suitability of different analysis techniques for the measure being assessed; andconsistent presentation of results to aid subsequent comparison of different studies. The full text of this paper may be found at: http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0395.pdf For the covering abstract see ITRD E145407.