title: The neuropsychological assessment of cognitive deficits considering measures of performance variability.
abstract: Neuropsychologists often face interpretational difficulties when assessing cognitive deficits, particularly in cases of unclear cerebral etiology. How can we be sure whether a single test score below the population average is indicative of a pathological brain condition or normal? In the past few years, the topic of intra-individual performance variability has gained great interest. On the basis of a large normative sample, two measures of performance variability and their importance for neuropsychological interpretation will be presented in this paper: the number of low scores and the level of dispersion. We conclude that low scores are common in healthy individuals. On the other hand, the level of dispersion is relatively small. Here, base rate information about abnormally low scores and abnormally high dispersion across cognitive abilities are provided to improve the awareness of normal variability and to serve clinicians as additional interpretive measures in the diagnostic process.
authors.affiliation: Department of Psychology, University of Bern, Bern CH-3012, Switzerland Neurological Rehabilitation Centre, Reha Rheinfelden, Rheinfelden CH-4310, Switzerland tannerceline@icloud.com.
authors.forename: Céline
authors.initials: C
authors.lastname: Tanner-Eggen
authors.affiliation: Neurological Rehabilitation Centre, Reha Rheinfelden, Rheinfelden CH-4310, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Balzer
authors.affiliation: Department of Psychology, University of Bern, Bern CH-3012, Switzerland.
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Perrig
authors.affiliation: Department of Neurology, Division of Cognitive and Restorative Neurology, Inselspital, Bern University Hospital, and University of Bern, Bern CH-3010, Switzerland.
authors.forename: Klemens
authors.initials: K
authors.lastname: Gutbrod
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001927:Brain Diseases / Q000150:complications*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D055815:Young Adult
keywords: Base rates; Dispersion; Low scores; Neuropsychological assessment; Normal variability