[Dementia Care Mapping-Japanese version(DCM-J) as a research evaluation method for measuring quality of life among elderly patients with dementia: reliability and validity of Well-being and Ill-being value].

AIM: Dementia Care Mapping is a behavior evaluation tool that can be used to measure and improve the quality of life of elderly patients with dementia. However, the reliability and validity of the Dementia Care Mapping-Japanese version (DCM-J) has not yet been established. Therefore, the purpose of this research was to clarify the reliability and validity of the Well-being and Ill-being (WIB) value of the DCM-J as a method for evaluating quality of life. METHODS: The study was conducted from April 1, 2005 to June 30, 2006. The participants included 130 elderly patients (men 31, women 99, average age 82.65+/-7.69 years) who were given a diagnosis of dementia. We established inter-rater reliability during a parallel observation method and also used test-retest for reliability. The correlation between the WIB value of the DCM-J and the Japanese Quality of Life Inventory for Elderly with Dementia (QOL-D) was used to establish criterion-related validity. RESULTS: Forty-nine (37.7%) subjects were given a diagnosis of dementia of Alzheimer's type, 80 (61.5%) had vascular dementia and 1 (0.8%) had dementia with Lewy bodies. The results showed correlation between the WIB value and social withdrawal measured by the behavioral category code (BCC) on the DCM-J and the three subscales of QOL-D: "interacting with surroundings", "expressing self", and "experiencing minimum negative behaviors". There was good internal consistency among these items. The interclass correlation coefficient was 82.32 (+/-5.85) for the WIB value of the DCM-J. The correlation coefficient of the retest, administered one week later, was 0.836 (p=0.001). The WIB value was significantly correlated with three sub-scales of QOL-D, and the correlation coefficient was greater than 0.53. CONCLUSION: We demonstrated that the WIB value of the DCM-J has good inter-rater reliability and test re-test reliability and criterion-related validity. In this study, the WIB value was shown to have similar reliability to the WIB value of the original DCM. Furthermore, our results suggest that the DCM-J could be useful for evaluating quality of life among elderly Japanese patients with dementia.