The validity and reliability of the Samsung                                           Dementia Questionnaire (SDQ)

J Korean Neurol Assoc > Volume 16(3); 1998 > Article

Journal of the Korean Neurological Association 1998;16(3): 307-314.

Samsung Dementia Questionnaire (SDQ)의 타당도와 신뢰도 평가

최성혜., 나덕렬. 강연욱. 이원용. 박병주*

성균관대학교 의과대학 신경과학교실. 서울대학교 의과대학 예방의학교실*

The validity and reliability of the Samsung Dementia Questionnaire (SDQ)

SH Choi, M.D., DL Na, M.D., Y Kang, Ph.D., WY Lee, M.D., BJ Park, M.D.*

Dept. of Neurology, College of Medicine, Sungkyunkwan University, Samsung Medical Center Dept. of Preventive Medicine, College of Medicine, Seoul National University*

Abstract

Background and Purpose: The Samsung Dementia Questionnaire (SDQ) was developed to screen dementia by asking an informant about an elderly person's everyday cognitive function. We conducted a case-control study to determine the effects of socio-demographic variables on the SDQ, and the validity and reliability of the SDQ for the diagnosis of dementia.
Methods: The questionnaire was administered to informants of 54 dementia patients (35 Alzheimer's disease, 19 vascular dementia) and 63 hospital control subjects. Frequency matching was done about age, sex and residence between the two groups. Informants were limited to intimate family member living with the subject. Test-retest data for the SDQ were obtained from 17 informants within a time interval averaging 31.12 days.
Results: The SDQ was not influenced by education level, age, or sex. Scores from the SDQ were found to correlate with the K-MMSE (r=-0.80). The area under the receiver operating characteristic (ROC) curve for the SDQ was 0.977 (S. E.=0.099). With respect to a diagnosis of dementia, the SDQ (cut-off point 17) had a sensitivity of 89% and a specificity of 94%. The SDQ was found to have high test-retest reliability (r=0.98).
Conclusion: The SDQ has high validity and test-retest reliability for the diagnosis of Alzheimer's disease and vascular dementia. It may be a useful tool for screening dementia. Keywords: Questionnaire, Dementia, Screening, Alzheimer disease, vascular dementia