Refined Measurement of Verbal Learning and Memory: Application of Item Response Theory to California Verbal Learning Test – Second Edition (CVLT-II) Learning Trials

Abstract

Abstract Objective This study was conducted to investigate how items contained within the California Verbal Learning Test – Second Edition (CVLT-II; Delis, D. C., Kramer, J. H., Kaplan, E., & Ober, B. A. (2000). California Verbal Learning Test (2nd ed.). San Antonio, TX: Psychological Corporation) learning trials function and to evaluate whether weighted scoring approaches might improve quantification of verbal memory. Method Archival data from 577 individuals (338 healthy young adults, 239 medical or psychiatric patients referred to a neuropsychology clinic) were obtained and evaluated using item response theory. Results The serial position effect was evident across trials, but was most evident in Trials 1, 2, and 3. CVLT-II Trial 5 was the most effective among the five learning trials in quantifying verbal memory, although it was most effective when measuring lower memory ability levels. In contrast, CVLT-II Trial 1 items had, on average, the highest difficulty levels. Various weighted scoring approaches did not appear incrementally helpful in improving prediction of memory performance. Conclusion Specific items and trials differentially discriminate between examinees with low levels of memory ability; it is important to thoroughly evaluate item properties of tests used in clinical decision-making.