Recruitment procedures and their impact on the prevalence of dementia - Results from the Leipzig Longitudinal Study of the Aged (LEILA75+)

Recruitment procedures may exert a considerable influence on the outcome of health surveys in the elderly. Their impact on the prevalence of dementia will be measured in an epidemiological field study in a sample of 1,692 randomly selected individuals (75+), Face-to-face interviews were conducted using SIDAM (structured interview for the diagnosis of dementia of Alzheimer type, multiinfarct dementia and dementias of other etiology according to ICD-10 and DSM-III-R), furthermore, proxy interviews were per formed with relatives of fragile and functionally dependent individuals, Considering face-to-face interviews of community-dwelling individuals, a prevalence of moderate and severe dementia of 5.3% was found, When including information on respondents by proxy and institutionalized individuals, the prevalence rate increased to 6.3 and 10.5%, respectively, It will be argued that covering the whole population in question and ensuring high response rates are central issues to minimize selection bias, Copyright (C) 2000 S. Karger AG, Basel.