Given finite resources, it is often necessary to make choices
among interventions. League tables list cost effectiveness results
from several different studies and, in theory, allow readers to
compare the cost effectiveness of different interventions. Several
such tables are available in the published literature, but, because
of the wide variation in methods used in the original studies,
these tables may be misleading if taken at face value.28 In one
league table, all results were standardised to a common currency
and attempts were made to ensure correct calculation of cost
effectiveness ratios to improve comparability of the results
across analyses.29 However, the assumptions made in the
individual analyses, such as the choice of comparator, were not
judged.