Validity of the Japanese version of Rivermead Behavioural Memory Test for evaluation of everyday memory function in patients with mild Alzheimer's disease

Objective: To validate the Japanese version of Rivermead Behavioural Memory Test (RBMT) in evaluating everyday memory function in patients with mild Alzheimer's disease (AD). Subjects and Methods: Subjects were 100 patients with probable AD of very mild or mild stages of dementia as measured by the Clinical Dementia Rating (CDR). Scores of the Japanese version of RBMT were correlated with scores of the Alzheimer's Disease Assessment Scale-Cognitive part (ADAS-J Cog) and of the Wechsler Memory Scale-Revised (WMS-R). The everyday disability caused by the impairment of memory function was also assessed with the Memory Checklist(CL), and was correlated with the RBMT scores. In addition, the diagnostic value of the RBMT was examined in 46 pairs of AD patients and healthy subjects; the patients were chosen from the present subjects and the healthy subjects from the participants in the previous RBMT standardization study as one-by-one matched for age, sex, and educational level. Results: Both of the total screening score and profile score of RBMT were significantly correlated with all of the weighted sum scores of verbal, visual, general, and delayed memory tests of the WMS-R and the word recall subtest score of the ADAS-J Cog. Both of the RBMT scores were also highly correlated with the CL score and the memory subscale of the CDR. In the analysis of the diagnostic accuracy, both of the RBMT scores correctly classified 98% of AD patients and 96% of normal volunteers by setting the cut-off scores of 6/5 for the total screening score and of 14/13 for the total profile score. Conclusions:The RBMT is a useful tool in evaluating everyday memory function in patients with mild AD. This test also accurately differentiates AD patients from healthy individuals.