Rochelle E Tractenberg1, Paul S Aisen. 1. Departments of Neurology, Biostatistics, Bioinformatics and Biomathematics, and Psychiatry, Georgetown University School of Medicine, Washington, D.C. 20057, USA. ret7@georgetown.edu
Abstract
AIMS: To estimate agreement among scores on three common assessments of cognitive function. METHOD: Baseline responses on the Alzheimer's Disease Assessment Scale - Cognitive, Clinical Dementia Rating, and the Mini-Mental State Examination were obtained from two clinical trials (n = 138 and n = 351). A graphical method of examining agreement, the means-difference or Bland-Altman plot, was followed by Levene's test of the equality of variance corrected for multiple comparison within each sample. RESULTS: 70-78% of variability was shared by one factor, suggesting that all three instruments reflect cognitive impairment. However, agreement among tests was significantly worse for individuals with greater-than-average, relative to individuals with less-than-average, cognitive impairment. CONCLUSIONS: Worse agreement between tests, as a function of increasing cognitive impairment, implies that interpretation of these tests and selection of coprimary cognitive impairment outcomes may depend on impairment level.
RCT Entities:
AIMS: To estimate agreement among scores on three common assessments of cognitive function. METHOD: Baseline responses on the Alzheimer's Disease Assessment Scale - Cognitive, Clinical Dementia Rating, and the Mini-Mental State Examination were obtained from two clinical trials (n = 138 and n = 351). A graphical method of examining agreement, the means-difference or Bland-Altman plot, was followed by Levene's test of the equality of variance corrected for multiple comparison within each sample. RESULTS: 70-78% of variability was shared by one factor, suggesting that all three instruments reflect cognitive impairment. However, agreement among tests was significantly worse for individuals with greater-than-average, relative to individuals with less-than-average, cognitive impairment. CONCLUSIONS: Worse agreement between tests, as a function of increasing cognitive impairment, implies that interpretation of these tests and selection of coprimary cognitive impairment outcomes may depend on impairment level.
Authors: P S Aisen; K L Davis; J D Berg; K Schafer; K Campbell; R G Thomas; M F Weiner; M R Farlow; M Sano; M Grundman; L J Thal Journal: Neurology Date: 2000-02-08 Impact factor: 9.910
Authors: E F J Meulen; B Schmand; J P van Campen; S J de Koning; R W Ponds; P Scheltens; F R Verhey Journal: J Neurol Neurosurg Psychiatry Date: 2004-05 Impact factor: 10.154
Authors: Sarah Tomaszewski Farias; Dan Mungas; Bruce R Reed; Deborah Cahn-Weiner; William Jagust; Kathleen Baynes; Charles Decarli Journal: Neuropsychology Date: 2008-07 Impact factor: 3.295
Authors: Rochelle E Tractenberg; Paul S Aisen; Myron F Weiner; Jeffrey L Cummings; Gregory R Hancock Journal: Alzheimers Dement Date: 2006-10 Impact factor: 21.566
Authors: Rochelle E Tractenberg; Myron F Weiner; Jeffrey L Cummings; Marian B Patterson; Leon J Thal Journal: J Neuropsychiatry Clin Neurosci Date: 2005 Impact factor: 2.198