Moreover, differences in the
relative difficulty of cases used in assessing a group of equivalently
experienced trainees can also lead to errors of measurement. This
problem can be partially addressed through careful selection of
cases and attention to the level of difficulty for each trainee. It is
also true that assessors themselves may rate cases as more or less
complex, depending on their level of expertise with such cases in
their own practice. Thus it is essential with all of these measures to
usemultiple observations as a single observation is a poor predictor
of a doctor’s performance in other settings with other cases