Intra-Individual Variability in Cognitive Performance Can Befuddle the Study of Cognitive Impairments and Decline

Szymon Zdanowski; Alieke Tieks; Bertus F Jeronimus; Marij Zuidersma

doi:10.3233/JAD-210304

Intra-Individual Variability in Cognitive Performance Can Befuddle the Study of Cognitive Impairments and Decline

J Alzheimers Dis. 2022;85(2):519-525. doi: 10.3233/JAD-210304.

Authors

Szymon Zdanowski¹, Alieke Tieks², Bertus F Jeronimus³, Marij Zuidersma²

Affiliations

¹ Department of Anaesthesiology and IntensiveTherapy, Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland.
² The Interdisciplinary Center Psychopathology and Emotion regulation (ICPE), University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
³ Department of Developmental Psychology, University of Groningen, Groningen, TheNetherlands.

Abstract

Using group-aggregated results and snapshot assessments of cognitive performance may prove problematic if the assessed construct shows substantial and rapid variation over time. To illustrate the significance of this issue, we analyzed cognitive performance data of ten older adults undergoing daily computerized cognitive assessments (CogState Brief Battery) for 36-93 days. In all cases, the day-to-day intra-individual variability was substantial when compared with group-level, between-person variability. This indicates that the results of studies using single snapshot assessments of cognitive functioning should be interpreted with caution. Additionally, group-aggregated measures of cognitive performance may not directly extrapolate to an individual.

Keywords: Attention; cognition; intra-individual variability; memory; reaction time; working memory.

Publication types

Letter
Research Support, Non-U.S. Gov't

MeSH terms

Activities of Daily Living
Aged
Aged, 80 and over
Cognition
Cognitive Dysfunction / diagnosis*
Cognitive Dysfunction / etiology*
Diagnosis, Computer-Assisted / methods*
Female
Humans
Male
Middle Aged
Neuropsychological Tests