Memory tests that are in a recall format have almost universally
measured accuracy in terms of the number of target items reported by the
examinee. However, this traditional scoring method can, in certain cases,
result in artificially inflated memory accuracy scores. That is, just as a
“yes” response bias and high false-positive rate on
recognition testing can artificially inflate a patient's hit rate,
so, too, a liberal response bias and high intrusion rate on recall testing
can artificially inflate a patient's level of target recall.
Recognition tests correct for this problem by using a discriminability
measure that provides a single score of hit rate relative to
false-positive rate; however, recall tests rarely provide a single score
of recall accuracy that corrects for intrusion rate. In the present study,
we examined the utility of a new recall discriminability measure that
analyzes target recall relative to intrusion rate. Patients with
Alzheimer's disease (AD) or Huntington's disease (HD) were
administered the CVLT–II, which provides both the traditional
measure of target recall and a new measure of recall discriminability. The
results indicate that the new recall discriminability measure was superior
to the traditional level of target recall measure in distinguishing the
recall performance of AD and HD patients. Implications of these results
for clinical practice and theories of memory disorder in dementia are
discussed. (JINS, 2005, 11, 708–715.)