The economic appraisal of transport projects: the incorporation of disabled access

The importance for disabled people of accessible transport is now widely recognised, as is the reality that this also benefits many non-disabled people. Many previous commentaries offer a qualitative perspective, but quantitative evidence, particularly of benefits to the population as a whole, has been lacking. This research, underpinned by the Social Model of disability, established that the absence of such evidence creates a barrier to the inclusion of disabled people in mainstream transport. Further, it demonstrates that there is a way to remove this barrier: by applying stated preference techniques, the benefits of providing access to transport systems can be robustly monetised and successfully incorporated into the economic appraisal of transport projects. A multiple-case study of tram systems investigated how practitioners currently incorporate disabled access into project appraisals. Analysis showed that isomorphic forces identified by new institutional theory have led to similarity in practice, with the effect that ways of incorporating the costs of disabled access are well established, but ways of incorporating the benefits remain unclear. Resulting benefit:cost ratios, often apparently unfavourable, may be misleading. A systematic literature review catalogued methods for valuing non-market goods, and from these identified methods transferable to disabled access. Stated preference, a method of monetisation common in the transport environment, emerged as an appropriate method, with discrete choice modelling a suitable technique. A discrete choice experiment enabled calculation of monetary values for platform-to-platform access at stations. Using a cross-section of the population and addressing socioeconomic factors such as age, disability, and attitudes to disabled people, willingness-to-pay figures were derived for access methods suited to disabled people‘s needs. Finally, these willingness-to-pay figures were incorporated into two appraisals. The amended benefit:cost ratios more accurately represent the value of access provision, and the figures incidentally enable the relative values of different access options to be distinguished.