Measurement and analysis of behavioural disturbance among community-dwelling and institutionalized persons with dementia.

Census data suggest that persons over 84 years of age represent the fastest growing segment of populations in most western nations. As advancing age remains the single strongest risk factor for dementia, prevalence rates are expected to increase substantially in coming years. This awareness underscores the need to more fully understand the clinical presentation of Alzheimer disease and other neurodegenerative disorders. The present study examines responses to the 28-item Dementia Behaviour Disturbance Scale (DBD; Baumgarten, Becker, & Gauthier, 1990) among a national sample of persons with dementia (PWD) in Canada. A 3-factor solution appears to best reflect DBD responses for both institutionalized and community-dwelling PWD. This finding is notable given that the former was significantly more impaired and presented with significantly greater levels of behavioural disturbance. Support for the factorial validity of these constructs is provided relative to caregiver burden and depressive symptomatology. Of note, only 14 of 28 DBD items were retained in our analyses; on this basis, we propose the use of an abridged version of the scale. These findings can be generalized with greater confidence given the random and representative nature of the PWD and caregiver samples.