Exploring the concurrent validity of the nationwide assessment of permanent nursing home residence in Denmark: A cross-sectional data analysis using two administrative registries

Background Many register studies make use of information about permanent nursing home residents. Statistics Denmark (StatD) identifies nursing home residents by two different indirect methods, one based on reports from the municipalities regarding home care in taken place in a nursing home, and the other based on an algorithm created by StatD. The aim of the present study was to validate StatD’s nursing home register using dedicated administrative municipality records on individual nursing home residents as gold standard.