Validity of the Finnish Care Register for Social Welfare in a nationwide cohort of people with Alzheimer's disease.

To assess the validity and completeness of the Care Register for Social Welfare among community-dwelling people with Alzheimer's disease in Finland. The study was carried out in the Medication Use and Alzheimer's disease (MEDALZ) study population, which includes 70,719 people who received a clinically verified diagnosis of Alzheimer's disease between 2005 and 2011 and the people matched with them for comparison ( The required level of assistance at discharge was recorded for 99.7% of people, diagnoses for 5.1% of the care periods and the discharge date for 100% of the completed care periods. Depending on the definition of long-term care, 6-10% of all long-term care periods included drug purchases during the study period.