Combining cost-benefit and multi-criteria analysis to prioritise a national road infrastructure programme

This paper develops and then applies a novel approach of combining cost-benefit analysis (CBA) and multi-criteria analysis (MCA) within a road infrastructure development programme with the aim to support the effective implementation of transport policy when prioritising projects. By incorporating CBA results into an MCA framework this approach retains the strengths of each appraisal method and provides a procedure for decision makers to create an initial ranking of projects which is consistent between all candidate investments and has a clear link to policy goals. We further develop an approach for an incremental analysis that eliminates mutually exclusive projects and allows decision makers to develop a cost-effective investment programme in compliance with their strategic goals. Stakeholder confidence in the outcome of any infrastructure investment ranking exercise is important and can be enhanced by an understanding of the robustness of the ranking to variations in key inputs to the assessment exercise. Two complementary perspectives on sensitivity testing are outlined which between them facilitate an assessment of the robustness of the project ranking obtained. The applicability of the approach has been successfully demonstrated for the National Secondary Road Network in Ireland.

► Presents a novel method of combining cost-benefit and multi-criteria analyses.
► Captures the strengths of both approaches to transport project assessment.
► Facilitates consistency with other assessments by the responsible authority.
► Develops a new approach to sensitivity testing and robustness analysis.