J Clin Neurol.  2020 Jan;16(1):145-153. 10.3988/jcn.2020.16.1.145.

Reliability and Validity of a Short Form of the Korean Dementia Screening Questionnaire-Cognition

• Kim A
• Kim S
• Park KW
• Park KH
• Youn YC
• Lee DW
• Lee JY
• Lee JH
• Jeong JH
• Choi SH
• Han HJ
• Kim S
• Na S
• Park M
• Yim HW
• Yang DW

• KMID: 2467797
• DOI: http://doi.org/10.3988/jcn.2020.16.1.145

Abstract

BACKGROUND AND PURPOSE
We aimed to determine the reliability and validity of a short form of the Korean Dementia Screening Questionnaire-Cognition (KDSQ-C) as a screening tool for cognitive dysfunction.
METHODS
This study recruited 420 patients older than 65 years and their informants from 11 hospitals, and categorized the patients into normal cognition, mild cognitive impairment, and dementia subgroups. The KDSQ-C was completed separately by the patients and their informants. We abstracted three components of the KDSQ-C and combined these components into the following four subscales: KDSQ-C-I (items 1-5, memory domain), KDSQ-C-II (items 1-5 & 11-15, memory domain+activities of daily living), KDSQ-C-III (items 1-5 & 6-10, memory domain+other cognitive domains), and KDSQ-C-IV (items 6-10 & 11-15, other cognitive domains+activities of daily living). The reliability and validity were compared between these four subscales.
RESULTS
A receiver operating characteristic (ROC) analysis of questionnaire scores provided by the patients showed that the areas under the ROC curves (AUCs) for the KDSQ-C, KDSQC-I, and KDSQ-C-II for diagnosing dementia were 0.75, 0.72, and 0.76, respectively; the corresponding AUCs for informant-completed questionnaires were 0.92, 0.89, and 0.92, indicating good discriminability for dementia.
CONCLUSIONS
A short form of the patient- and informant-rated versions of the KDSQ-C (KDSQ-C-II) is as capable as the 15-item KDSQ-C in screening for dementia.

Keyword

cognition; dementia; self report; self-assessment; questionnaire

MeSH Terms

Area Under Curve
Cognition
Dementia*
Humans
Mass Screening*
Memory
Mild Cognitive Impairment
Reproducibility of Results*
ROC Curve
Self Report
Self-Assessment

Figure

• 

  Fig. 1 ROC curves. A: ROC curves for normal cognition vs. dementia for MMSE-DS, p-KDSQ-C, p-KDSQ-C-I, p-KDSQ-C-II, p-KDSQ-C-III, and p-KDSQ-C-IV. B: ROC curves for normal cognition vs. dementia for MMSE-DS, i-KDSQ-C, i-KDSQ-C-I, i-KDSQ-C-II, i-KDSQ-C-III, and i-KDSQ-C-IV. i-KDSQ-C: informant-rated KDSQ-C, KDSQ-C: Korean Dementia Screening Questionnaire-Cognition, KDSQ-C-I: items 1–5, memory domain, KDSQ-C-II: items 1–5 & 11–15, memory domain+activities of daily living, KDSQ-C-III: items 1–5 & 6–10, memory domain+other cognitive domains, KDSQ-C-IV: items 6–10 & 11–15, other cognitive domains+activities of daily living, MMSE-DS: Mini Mental State Examination-Dementia Screening, p-KDSQ-C: patient-rated KDSQ-C, ROC: receiver operating characteristic.

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