OBJECTIVE: This study examined between- and within-subject stability of cognitive performance in individuals with chronic schizophrenia. METHODS: Thirty individuals with schizophrenia and 20 healthy controls matched by age, sex, education, and estimated IQ underwent repeated cognitive assessments at baseline and 30 days using computerized tests of psychomotor function, visual attention/information processing, non-verbal learning, and executive function. RESULTS: Compared to healthy controls, individuals with schizophrenia scored lower on all cognitive measures and demonstrated greater variability in cognitive performance. Within-subject variability in cognitive performance in both the schizophrenia and healthy control groups remained stable at brief (i.e., hours) and intermediate (i.e., one month) assessments. CONCLUSIONS: These results demonstrate the stability of between- and within-subject variability in cognitive performance in schizophrenia, and suggest that variability in cognitive performance may reflect an inherent characteristic of the disorder, rather than differences in test-retest reliability/error of cognitive measures.
OBJECTIVE: This study examined between- and within-subject stability of cognitive performance in individuals with chronic schizophrenia. METHODS: Thirty individuals with schizophrenia and 20 healthy controls matched by age, sex, education, and estimated IQ underwent repeated cognitive assessments at baseline and 30 days using computerized tests of psychomotor function, visual attention/information processing, non-verbal learning, and executive function. RESULTS: Compared to healthy controls, individuals with schizophrenia scored lower on all cognitive measures and demonstrated greater variability in cognitive performance. Within-subject variability in cognitive performance in both the schizophrenia and healthy control groups remained stable at brief (i.e., hours) and intermediate (i.e., one month) assessments. CONCLUSIONS: These results demonstrate the stability of between- and within-subject variability in cognitive performance in schizophrenia, and suggest that variability in cognitive performance may reflect an inherent characteristic of the disorder, rather than differences in test-retest reliability/error of cognitive measures.
Authors: Dustin Hammers; Elizabeth Spurgeon; Kelly Ryan; Carol Persad; Judith Heidebrink; Nancy Barbas; Roger Albin; Kirk Frey; David Darby; Bruno Giordani Journal: Am J Alzheimers Dis Other Demen Date: 2011-06-01 Impact factor: 2.035
Authors: David R Roalf; Ruben C Gur; Laura Almasy; Jan Richard; R Sean Gallagher; Konasale Prasad; Joel Wood; Michael F Pogue-Geile; Vishwajit L Nimgaonkar; Raquel E Gur Journal: Schizophr Bull Date: 2012-08-27 Impact factor: 9.306
Authors: Martina Hubacher; Marcus Weiland; Pasquale Calabrese; Gabriela Stoppe; Markus Stöcklin; David Fischer-Barnicol; Klaus Opwis; Iris-Katharina Penner Journal: Psychiatry J Date: 2013-02-26