Cluster subtypes on the California Verbal Learning Test-Second Edition (CVLT-II) in a traumatic brain injury sample

Subtypes of learning and memory on the California Verbal Learning Test-Second Edition (CVLT-II; Delis, Kramer, Kaplan, & Ober, 2000) were examined in a clinical sample of 223 persons with traumatic brain injury (TBI), screened to remove individuals with complicating premorbid (e.g., psychiatric) or comorbid (e.g., financial compensation-seeking) histories. The z scores from 4 key CVLT-II variables were entered into a two-stage cluster analysis. These variables were selected to represent 4 latent constructs, identified in a recent confirmatory factor analysis: List A1 (Attention Span), List A5 (Learning Efficiency), Long Delay Free Recall (Delayed Memory), and False Positives (Inaccurate Memory). Six reliable subtypes were found (similar to those in the standardization sample) that were differentiated by both level and pattern of performance, with differences in level of performance meaningfully related to length of coma. In conclusion, the impact of TBI on CVLT-II performance can be manifested in various patterns that are not specifically unique, but are affected by injury severity.