Although the cueing effects inherent in conventional multiple choice q
uestions (MCQs) present serious limitations, this format continues to
dominate testing programmes. The present study was undertaken to estim
ate the effects of cueing when MCQs are used to test medical students,
and to evaluate the reliability, validity and feasibility of an alter
native testing format. Equivalent items in both MCQ and open-ended, or
uncued (Un-Q), formats were administered to 34 third- and fourth-year
medical students. The students' mean % correct score on the MCQs was
11 percentage points higher than their mean level of performance on eq
uivalent Un-Qs. When a second set of more difficult items was administ
ered to 16 of these students, their mean performance on the MCQ items
was 22 percentage points higher than their performance on equivalent U
n-Qs. The results support the feasibility of large group administratio
n of tests constructed in an open-ended format that can be scored by c
omputer. Not only is this format equally reliable and economical when
compared with the MCQ, but it also provides important advantages that
strengthen its face validity. The Un-Q format can be used to test eith
er simple recall or certain higher level problem-solving skills that c
annot be tested by MCQs. Even more important, the results also suggest
that the Un-Q format may be a more effective discriminator of academi
cally marginal examinees.