Prevalence and Level of Diagnosis of Dementia in a Population-based Sample in the County of Trøndelag

To investigate and make valid estimates of the occurrence of dementia and the most common subtypes of dementia in Trøndelag, and transfer these figures to estimates of the occurrence of dementia in Norway as a whole, by age, sex and severity of dementia. Furthermore, the proportion of people without dementia diagnosis among those with dementia will be examined. The investigators will further investigate whether there are differences in dementia prevalence between males and females and educational groups and look at factors associated with a lack of diagnosis.