[Critical observations on measuring quality of life of persons suffering from dementia].

The assessment of quality of life (QoL) in patients suffering from dementia is increasingly called for by public health authorities, particularly for pharmacological intervention studies. From a clinical point of view, until now a critical discussion about determining the QoL of dementia patients has scarcely taken place. The extent to which a demented patient may be able to assess his or her own QoL is analysed with regard to the specific deficits associated with the dementia syndrome. Although a subjective assessment represents the gold standard of Qol measurement, the capacity to provide a reliable subjective QoL estimation is limited in dementia patients. Given the present state of knowledge, it seems reasonable to adhere to objectively measurable data. The question of QoL in dementia must be solved normatively and cannot be based on the subjective assessment of cognitively impaired persons.