Improving Transport Project Appraisals
In the Islamic Countries
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requirement for all interventions that require government approval. For interventions that do
not require government approval, the guidance serves as a best practice guide.
Since 2000, it has become more widely recognised in government that, where quantities can be
valued in monetary terms, MCA is not a substitute for CBA, but it may be a complementary tool.
Using the supplementary guidance on multi-criteria decision analysis24, options can be ranked
and a preferred option identified. A common aspect of MCA is a performance matrix, in which
each row describes an option and each column describes the performance of the options against
each criterion. The most common way to combine scores on criteria, and relevant weights
between criteria, is to calculate a simple weighted average of scores. The weights and scores are
determined by the MCA performer. The subjectivity related to this judgement can be a matter of
concern. In some cases it might be possible to include ‘objective’ data such as observed prices in
the establishment of weights and scores.
2.2.4 Content
As mentioned above, for transport project appraisals there is a nationwide obligation to carry
out CBA. Transport appraisal draws together information on a wide range of impacts – it does
not just consider the direct impacts on the transport users and service providers affected by the
intervention, but also the impacts of the intervention on the environment, wider society and
government. Analysts should seek to place a monetary value on as many of the impacts as
possible to allow a direct comparison between the costs and benefits of the intervention. To
assist analysts involved in transport appraisal, WebTAG provides guidance to enable option
development and analysis; and the appraisal of impacts (costs and benefits) produced by each
option. The results of an appraisal are summarised in an Appraisal Summary Table. Such a
summary table, together with the impacts that are considered, is presented i
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