CROSS-NATIONAL INTERRATER RELIABILITY OF DEMENTIA DIAGNOSIS IN THE ELDERLY AND FACTORS ASSOCIATED WITH DISAGREEMENT

Thirteen researchers from five centers in Australia, Germany, the Neth erlands, United Kingdom, and United States applied DSM-III-R and Clini cal Dementia Rating (CDR) syndrome-level dementia criteria to written vignettes of 100 elderly people identified in clinics or community sur veys. Subjects ranged in type from cognitively intact to severely deme nted and many were also frail, partially sighted, or deaf. This paper concerns reliability within and between centers, and the relationship between reliability and factors such as diagnostic criteria, dementia severity, and respondents' clinical characteristics. Within-center int errater reliability was high, more so for ''yes-no'' DSM-III-R diagnos es than the multi-level CDR. Between-center rates were lower but still moderate to good. Concordance was lower for intermediate dementia lev els than for no dementia and severe dementia. Physical disability made an additional contribution to uncertainty but deafness, poor vision, anxiety, and depression had no discernible effects. Reliability levels are likely to be lower in representative aged populations than in car efully selected clinical groups.