Background:The validity of dementia diagnoses in the Danish nationwide hospital registers was evaluated to determine the value of these registers in epidemiological research about dementia. Methods: Two hundred patients were randomly selected from 4,682 patients registered for the first time with a dementia diagnosis in the last 6 months of 2003. The patients’ medical journals were reviewed to evaluate if they fulfilled ICD-10 and/or DSM-IV criteria for dementia and specific dementia subtypes. The patients who were still alive in 2006 were invited to an interview. Results: One hundred and ninety-seven journals were available for review and 51 patients were interviewed. A registered diagnosis of dementia was found to be correct in 169 (85.8%) cases. Regarding dementia subtypes, the degree of agreement between the registers and the results of the validating process was low with a kappa of 0.36 (95% CI 0.24–0.48). Conclusion: The validity of dementia syndrome in the Danish hospital registers was high and allows for epidemiological studies about dementia. Alzheimer’s disease, although underregistered, also had a good validity once the diagnosis was registered. In general, other ICD-10 dementia subtypes in the registers had a low validity and are less suitable for epidemiological research.
© 2007 S. Karger AG, Basel
- Dementia diagnosis
- Danish register
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Thien Kieu Thi Phung, MD
Memory Disorders Research Group, Section 6131, Department of Neurology
The Neuroscience Centre, Copenhagen University Hospital Rigshospitalet
9 Blegdamsvej, DK–2100 Copenhagen (Denmark)
Tel. +45 35 45 62 47, Fax +45 35 45 24 46, E-Mail firstname.lastname@example.org
Accepted: May 14, 2007
Published online: August 10, 2007
Number of Print Pages : 9
Number of Figures : 0, Number of Tables : 6, Number of References : 34
Dementia and Geriatric Cognitive Disorders
Vol. 24, No. 3, Year 2007 (Cover Date: August 2007)
Journal Editor: Chan-Palay, V. (New York, N.Y.)
ISSN: 1420–8008 (print), 1421–9824 (Online)
For additional information: http://www.karger.com/DEM
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