Relatives' descriptions of changes in symptoms of dementia of the Alzheimer type: a comparison of retrospective and concurrent ratings.

Although relatives' retrospective reports are often used in characterizing the onset and progression of symptoms in dementia of the Alzheimer type (DAT), little is known about the accuracy of these accounts. The primary purpose of this paper is to summarize preliminary data obtained from relatives in an ongoing family study of DAT. Preliminary findings suggest there is rough reliability to relatives' recall of the progression of symptoms over time. This observation is discussed in relation to literature from other areas (e.g. child development, psychopathology) where the reliability of relatives' retrospection has been more thoroughly examined.