Evidence of systematic attenuation in the measurement of cognitive deficits in schizophrenia.

ABSTRACT: Cognitive tasks that are too hard or too easy produce imprecise measurements of ability, which, in turn, attenuates group differences and can lead to inaccurate conclusions in clinical research. We aimed to illustrate this problem using a popular experimental measure of working memory-the N-back task-and to suggest corrective strategies for measuring working memory and other cognitive deficits in schizophrenia. Samples of undergraduates (n = 42), community controls (n = 25), outpatients with schizophrenia (n = 33), and inpatients with schizophrenia (n = 17) completed the N-back. Predictors of task difficulty-including load, number of word syllables, and presentation time-were experimentally manipulated. Using a methodology that combined techniques from signal detection theory and item resp

SUBMITTER: Thomas ML 

PROVIDER: S-EPMC5378601 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature