Reliability and Validity of an Algorithm for the Diagnosis of Normal Cognition, Mild Cognitive Impairment, and Dementia: Implications for Multicenter Research Studies

Author(s)

Ranjan Duara, Mount Sinai Medical CenterFollow
David A. Loewenstein, University of Miami
Maria Greig
Amarilis Acevedo, Nova Southeastern UniversityFollow
Elizabeth Potter, Mount Sinai Medical Center, Miami Beach
Jason Appel, Mount Sinai Medical Center, Miami Beach
Ashok Raj, Harvard Medical Center
John Schinka
Elizabeth Schofield, University of South Florida
Warren Barker, Mount Sinai Medical Center, Miami BeachFollow
Yougui Wu, University of South Florida
Huntington Potter, University of South Florida

Document Type

Article

Publication Title

The American Journal of Geriatric Psychiatry

ISSN

1064-7481

Publication Date

4-2010

Abstract

METHODS:

The AlgDx combines the PhyDx with the NPDx, using a diagnostic algorithm that provides cognitive diagnoses, as defined by the National Alzheimer Coordinating Center/Uniform Data Set nomenclature. Reliability of the AlgDx was assessed in 532 community-dwelling elderly subjects by its concordance with the ConsDx and association with two biomarkers, medial temporal atrophy (MTA) scores of brain magnetic resonance imaging scans, and Apolipoprotein E (ApoE)-epsilon4 genotype.

RESULTS:

A high degree of concordance was observed between ConsDx and AlgDx with a weighted Cohen's kappa of 0.84. Concordance of the AlgDx to the same ConsDx categories ranged from 85% to 92%. Excellent discriminative validity was observed using AlgDx, MTA scores, and ApoE-epsilon4 allele frequencies, each of which distinguished subjects with amnestic MCI and dementia from normal subjects.

CONCLUSION:

The AlgDx of normal cognition, MCI, and dementia is a valid alternative that reduces time, effort, and biases associated with the ConsDx. The inherent reliability of a fixed algorithm, together with its efficiency and avoidance of individual bias, suggests the AlgDx may be used in longitudinal, multisite clinical trials, and population studies of MCI and dementia.

Volume

18

Issue

4

First Page

363

Last Page

370

NSUWorks Citation

Duara, R., Loewenstein, D. A., Greig, M., Acevedo, A., Potter, E., Appel, J., Raj, A., Schinka, J., Schofield, E., Barker, W., Wu, Y., Potter, H. (2010). Reliability and Validity of an Algorithm for the Diagnosis of Normal Cognition, Mild Cognitive Impairment, and Dementia: Implications for Multicenter Research Studies. The American Journal of Geriatric Psychiatry, 18(4), 363-370.
Available at: https://nsuworks.nova.edu/cps_facarticles/564