Differential distributions of sociodemographic characteristics and cognitive impairment in responders and non-responders may result in a biased prevalence estimate of dementia based on responders only.
Responders (n=2191) to a cross-sectional, two-stage community study were compared with regard to sociodemographic characteristics and cognition with three subgroups of non-responders : (A) subjects who refused to participate (n=369), (B) subjects who were too ill or who had died prior to the screening (n=72) and (C) subjects who had moved out of the study region or were not traceable (n=23).
Prevalence estimates specific for age and housing situation in responders and physicians'ratings of cognitive impairment were used to estimate the prevalence of dementia among non-responders.
Group A differed from responders in age and housing situation, group B in age, housing and cognition, and group C only in age.
Separate prevalence estimates of dementia based on age, housing and cognition yielded figures for group A between 4.9% and 7.2%, for group B between 13.1% and 19.1%, and for group C between 2.6% and 4.2%. Joined with the prevalence rate among responders (6.5%) the best possible point estimate of the prevalence of dementia in the target population lies between 6.4% and 6.9%, i.e. within the 95% confidence interval (Cl) of the prevalence among responders (5.4-7.5%). (...)
Mots-clés Pascal : Démence Alzheimer, Non réponse, Réponse, Evaluation, Statut socioéconomique, Age, Sexe, Statut conjugal, Epidémiologie, Prévalence, Méthodologie, Biais méthodologique, Vieillard, Homme, Pays Bas, Europe, Etude comparative, Système nerveux pathologie, Système nerveux central pathologie, Encéphale pathologie, Maladie dégénérative
Mots-clés Pascal anglais : Alzheimer disease, Non response, Response, Evaluation, Socioeconomic status, Age, Sex, Marital status, Epidemiology, Prevalence, Methodology, Methodological bias, Elderly, Human, Netherlands, Europe, Comparative study, Nervous system diseases, Central nervous system disease, Cerebral disorder, Degenerative disease
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0534225
Code Inist : 002B30A01A1. Création : 13/02/1998.