Titolo
Brian L. Brooks, Alberta Children’s Hospital and University of Calgary
Esther Strauss, University of Victoria
Elisabeth M. S. Sherman, Alberta Children’s Hospital and University of Calgary
Grant L. Iverson, University of British Columbia and British Columbia Mental Health and Addiction Services
Daniel J. Slick, Alberta Children’s Hospital and University of Calgary
Canadian Psychology © 2009 Canadian Psychological Association, 2009, Vol. 50, No. 3, 196–209
DOI: 10.1037/a0016066
Abstract
The goal of this article is to discuss psychometric issues that are important in neuropsychological assessment and to present some recent advances in empirically derived interpretation methods. The article is divided into four main sections. The first two sections provide an overview of some of the basic psychometric concepts that make up the foundation of assessment. The first section presents an overview of how the adequacy of the normative sample and the shape of the score distribution can impact the interpretation of test performance. The second section presents a review of the role of measurement error and considers how the level of scores, their rank in the distribution, and the presence of ceiling or floor effects can impact interpretation. The third section explores the issue of normal variability and the prevalence of abnormal” test scores in healthy people. The final section provides an overview of various methods for interpreting change in test performance over time. The authors present this psychometric information in a manner that should be easily understood by most clinicians, with examples that employ commonly used neuropsychological tests, such as the Wechsler Adult Intelligence Scale–Third Edition (WAIS-III; Wechsler, 1997a), Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV; Wechsler, 2008), Wechsler Memory Scale–Third Edition (WMS-III; Wechsler, 1997b), Wechsler Memory Scale–Fourth Edition (WMS-IV; Wechsler, 2009), Children’s Memory Scale (CMS; Cohen, 1997), California Verbal Learning Test–Second Edition (CVLT-II; Delis, Kramer, Kaplan, & Ober, 2000), and the Neuropsychological Assessment Battery (NAB; Stern & White, 2003).
Keywords
neuropsychology, psychometrics, test selection, interpretation, assessment