Cross‐national interrater agreement on the clinical diagnostic criteria for dementia

Abstract

We assessed the interobserver agreement on the clinical diagnosis of dementia syndrome and dementia subtypes as part of a cross-national project on the prevalence of dementia. Fourteen clinicians from the participating countries (Canada, Chile, Malta, Nigeria, Spain, and the United States) independently assessed the diagnosis of 51 patients whose clinical information was in standard records written in English. We used the DSM-III-R and ICD-10 criteria for dementia syndrome, the NINCDS-ADRDA criteria for Alzheimer's disease (AD), and the ICD-10 criteria for other dementing diseases, and measured interobserver agreement. We found comparable levels of agreement on the diagnosis of dementia using the DSM-III-R (kappa = 0.67) as well as the ICD-10 criteria (kappa = 0.69). Cognitive impairment without dementia was a major source of disagreement (kappa = 0.10). The kappa values were 0.58 for probable AD, 0.12 for possible AD, and rose to 0.72 when the two categories were merged. The interrater reproducibility of the diagnosis of vascular dementia was 0.66 in terms of kappa index; the diagnoses of other dementing disorders as a whole reached a kappa value of 0.40. This study suggests that clinicians from different cultures and medical traditions can use the DSM-III-R and the ICD-10 criteria for dementia effectively and thus reliably identify dementia cases in cross-national research. The interrater agreement on the diagnosis of dementia might be improved if clear-cut guidelines in the definition of cognitive impairment are provided. To improve the reliability of AD diagnosis in epidemiologic studies, we suggest that the NINCDS-ADRDA "probable" and "possible" categories be merged.

The Rowland Universal Dementia Assessment Scale (RUDAS) and the Folstein MMSE in a multicultural cohort of elderly persons

“…The diagnosis of dementia may be problematic in culturally heterogeneous populations (Prince, 2000), particularly as there is no gold standard for diagnosis. However, all decisions were based on DSM-IV criteria, which have the advantage of broad acceptance and good reproducibility (Baldereschi et al, 1994). Furthermore, our subjects with dementia tended toward more severe disease, had an informant present in 92% of cases, and were all assessed by an experienced geriatrician (J.T.R.…”

Inter-Rater Agreement in the Clinical Diagnosis of Cognitive Status: Data from the Neurological Disorders in Central Spain 2 Pilot Study

“…We found that neurologists involved in the NEDICES-2 study achieved an overall substantial agreement when they applied the core clinical criteria for all-cause dementia of NIA-AA [9] and Winblad et al [10] criteria to diagnose cognitive status considering 3 categories: dementia, MCI and normal cognition. Hogervorst et al [7] described an almost perfect agreement (κ = 0.9) on the absence or presence of dementia between 2 independent medical doctors, using NINCDS/ADRDA criteria to classify 82 elderly, while the agreement was lower in the population survey carried out by Fratiglioni et al [26], with κ = 0.54 using DSM-III-R criteria and in the cross-national survey carried out by Baldereschi et al [6] with κ = 0.67 and 0.69 using DSM-III-R and ICD-10 criteria respectively. To our knowledge, concordance studies on clinical diagnosis of all-cause dementia and Alzheimer's disease using the new NIA-AA criteria have not been previously published.…”

“…Although some biological markers have been recently described for Alzheimer's disease [1], the diagnosis of dementia is still based on clinical criteria. Diagnostic and Statistical Manual of Mental disorders, Revised Third Edition (DSM-III-R) criteria [2] and fourth edition (DSM-IV) ones [3], International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) [4] and those of National Institute of Neurological and Communicative Disorders and the stroke and the Alzheimer's disease and related disorders Association (NINCDS-ADRA) [5] have improved diagnostic accuracy, with different inter-rater agreement in previously performed studies [6,7,8]. …”

Do experienced diagnosticians agree about the diagnosis of dementia from survey data? The effects of informants' reports and interviewers' vignettes

“…Previous studies have examined the interrater reliability of diagnosis of dementia (Baldereschi et al, 1994) or of Alzheimer's disease (Lopez et al, 1990) using the kappa statistic, but the data studied were medical records (Kukull et al, 1990) or written vignettes derived from the records (O'Connor et al, 1996), whereas here the raters (diagnosticians) were presented with coded data which had been collected for computer processing from interviews with a random sample of elderly people and their relatives. The aim in the broadest sense was to consider the diagnostic process preliminary to the calculation of rates during a population survey of cognitive decline and dementia, by studying in some detail how experienced diagnosticians with varied backgrounds independently interpreted the data, how far they agreed with each other and to what extent their opinions were in¯uenced by informants' reports and by brief narrative vignettes written by the interviewers after each interview.…”