title: Frequency of mental disorders in old age. Examples of comparability of epidemiological investigations in relation to utility in planning.
abstract: Due to the increase in the number of old people, diseases of old age have acquired more and more importance. In estimating the need for psychiatric hospitals and nursing homes, epidemiological investigations are necessary. Only relatively few population investigations of the old-age population have been carried out, and most of these have been carried out in countries in Northern Europe, which are closely related culturally and socially. In the present paper nine investigations are described in relation to certain central factors which include the purpose of the investigation, description of the population, selection of probands, and statistical concepts used, the collection of data, and the main results. Seven of the investigations give results in the form of prevalence, two investigations calculate incidence and morbidity risk. It is concluded that comparison of the various results is difficult as most of the authors have not intended their investigations for mutual comparison. It is clear that there are many dissimilarities in the milieus involved, in the methods used, in the prerequisites of the interviewers and assessors, and in the classification of the results. The investigations presented have been used for evaluation of prognosis and planning of care for the old-age population. It must be said that an investigation is an expression of local truth and as such often usable in local planning, but on the other hand it is not often possible to utilize results from investigations carried out in outside regions for more than a rough basis for local prognosis and local planning. It must therefore be stressed that in future investigations more standardized methods and better correlated descriptions are necessary.
mesh_terms: D000367:Age Factors; D000368:Aged; D003704:Dementia / Q000453:epidemiology; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology*; D009497:Neurotic Disorders / Q000453:epidemiology; D012537:Scandinavian and Nordic Countries; D006113:United Kingdom