Hostname: page-component-7c8c6479df-nwzlb Total loading time: 0 Render date: 2024-03-28T10:47:19.087Z Has data issue: false hasContentIssue false

Validation of a French Version of an Informant-Based Questionnaire as a Screening Test for Alzheimer's Disease

Published online by Cambridge University Press:  02 January 2018

Samuel Law
Affiliation:
Department of Medicine
Christina Wolfson*
Affiliation:
Department of Epidemiology & Biostatistics, McGill University, Montréal, Canada H3T 1E2
*
Dr Wolfson, Centre for Clinical Epidemiology and Community Studies, Rm A 127, Sir Mortimer B. Davis Jewish General Hospital, 3755, Chemin de la Côte Ste-Catherine, Montréal, Quebec, Canada H3T 1E2

Abstract

Background

Development of informant-based screening tests for dementia is an emerging field. The reliability and validity of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), an instrument that screens for dementia in general, have been established. We conducted a study to validate a French version of the IQCODE as a screening test for Alzheimer's dementia in the elderly living in the community.

Method

In the Canadian Study of Health and Aging, subjects were screened in their own homes using the Modified Mini-Mental State Exam (3-MS). Those who screened positive, along with a sample of subjects who screened negative, were referred for a complete clinical examination. In Quebec, an informant was asked to complete the French version, IQCODE (F), at that time. Based on the final clinical diagnoses, performances of the IQCODE (F) and Mini-Mental State Examination (MMSE, converted from 3-MS) in screening for Alzheimer's disease were evaluated.

Results

Of the 237 subjects, the mean IQCODE (F) score was 3.4 (s.d. = 0.6), on a 5-point scale (1 = improvement in condition over the past 10 years, 5 = marked deterioration, 3 = no change). The mean MMSE score was 23.1 (s.d. = 4.5). The scores on the two scales were correlated (r = –0.44, P < 0.001). The IQCODE (F) scores were unrelated to education (r = –0.07, P > 0.3) in contrast to the MMSE scores (r = 0.28, P < 0.001). With respect to a diagnosis of probable Alzheimer's disease, the IQCODE (F) (cut-off point 3.6) had a sensitivity of 75% and a specificity of 95.6%. The sensitivity and specificity of the MMSE (cut-off point 23) were 70% and 82.3% respectively.

Conclusion

The findings of the IQCODE (F) are consistent with those of the English version in correlation with the MMSE and apparent freedom from educational bias. The IQCODE is superior to the MMSE as a screening test for probable Alzheimer's disease in the elderly living in the community. It may be a useful addition to the screening tests already available, especially for the less well educated.

Type
Papers
Copyright
Copyright © 1995 The Royal College of Psychiatrists 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Anthony, J. C., LeResche, L., Niaz, U., et al (1982) Limits of the ‘Mini-Mental State’ as a screening test for dementia and delirium among hospital patients. Psychological Medicine, 12, 397408.CrossRefGoogle ScholarPubMed
Canadian Study of Health and Aging (1994) The Canadian study of health and aging: Study methods and prevalence of dementia in Canada. Canadian Medical Association Journal, 150, 899913.Google Scholar
Folstein, M. F., Folstein, S. E. & McHugh, P. R. (1975) Mini-mental state – a practical method for grading the mental state of patients for the clinician. Journal of Psychiatric Research, 12, 189198.CrossRefGoogle Scholar
Henderson, A. S. (1986) The epidemiology of Alzheimer's disease. British Medical Bulletin, 42, 310.CrossRefGoogle ScholarPubMed
Jagger, C., Clarke, M., Anderson, J., et al (1992) Misclassification of dementia by the Mini-Mental State Examination – are education and social class the only factors? Age and Aging, 21, 401411.CrossRefGoogle ScholarPubMed
Jorm, A. F., Scott, R., Cullen, J. S., et al (1991) Performance of the informant questionnaire on cognitive decline in the elderly (IQCODE) as a screening test for dementia. Psychological Medicine, 21, 785790.CrossRefGoogle ScholarPubMed
McKhann, G., Drachman, D., Folstein, M., et al (1984) Clinical diagnosis of Alzheimer's disease: report of the NINCDS-ADRDA work group under the auspices of Department of Health and Human Services Task force on Alzheimer's disease. Neurology, 3, 939944.CrossRefGoogle Scholar
O'Connor, D. W. (1990) The contribution of CAMDEX to the diagnosis of mild dementia in community surveys. Psychiatric Journal of University of Ottawa, 15, 216220.Google Scholar
Ritchie, K. & Fuhrer, R. (1992) A comparative study of the performance of screening tests for senile dementia using receiver operating characteristics analysis. Journal of Clinical Epidemiology, 45, 627637.CrossRefGoogle ScholarPubMed
Teng, E. L. & Chui, H. C. (1987) The modified mini-mental state (3-MS) examination. Journal of Clinical Psychiatry, 48, 314318.Google Scholar
Submit a response

eLetters

No eLetters have been published for this article.