Dataset Information

Validation and diagnostic accuracy of the Alzheimer's questionnaire.

ABSTRACT:

Background

accurately identifying individuals with cognitive impairment is difficult. Given the time constraints that many clinicians face, assessment of cognitive status is often not undertaken. The intent of this study is to determine the diagnostic accuracy of the Alzheimer's questionnaire (AQ) in identifying individuals with mild cognitive impairment (MCI) and AD.

Methods

utilising a case-control design, 300 [100 AD, 100 MCI, 100 cognitively normal (CN)] older adults between the ages of 53 and 93 from a neurology practice and a brain donation programme had the AQ administered to an informant. Diagnostic accuracy was assessed through receiver-operating characteristic analysis, which yielded sensitivity, specificity and area under the curve (AUC).

Results

the AQ demonstrated high sensitivity and specificity for detecting MCI [89.00 (81.20-94.40)]; [91.00 (83.60-65.80)] and AD [99.00 (94.60-100.00)]; [96.00 (90.10-98.90)]. AUC values also indicated high diagnostic accuracy for both MCI [0.95 (0.91-0.97)] and AD [0.99 (0.96-1.00)]. Internal consistency of the AQ was also high (Cronbach's alpha = 0.89).

Conclusion

the AQ is a valid informant-based instrument for identifying cognitive impairment, which could be easily implemented in a clinician's practice. It has high sensitivity and specificity in detecting both MCI and AD and allows clinicians to quickly and accurately assess individuals with reported cognitive problems.

SUBMITTER: Malek-Ahmadi M

PROVIDER: S-EPMC3335371 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Publications

Validation and diagnostic accuracy of the Alzheimer's questionnaire.

Malek-Ahmadi Michael M Davis Kathryn K Belden Christine C Laizure Brecken B Jacobson Sandra S Yaari Roy R Singh Upinder U Sabbagh Marwan N MN

Age and ageing 20120223 3

<h4>Background</h4>accurately identifying individuals with cognitive impairment is difficult. Given the time constraints that many clinicians face, assessment of cognitive status is often not undertaken. The intent of this study is to determine the diagnostic accuracy of the Alzheimer's questionnaire (AQ) in identifying individuals with mild cognitive impairment (MCI) and AD.<h4>Methods</h4>utilising a case-control design, 300 [100 AD, 100 MCI, 100 cognitively normal (CN)] older adults between t ...[more]

PMID: 22367356

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Dataset Information

Validation and diagnostic accuracy of the Alzheimer's questionnaire.

Background

Methods

Results

Conclusion

Publications

Validation and diagnostic accuracy of the Alzheimer's questionnaire.

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