Data sources
death, Death
DISEASES
All residents in Denmark receive a unique and permanent civil registration number at birth or immigration that enables individual-level linkage between nationwide registries and the electronic case report from the NorthStar study. Baseline data including demographic variables, clinical biochemistry, left ventricular ejection fraction, and NT-proBNP levels were available from the trial’s electronic case report form. For this extended follow-up analysis, we further obtained data from 1) the Danish Civil Registration System registry (sex, date of birth, immigration, emigration, and vital status), 2) the Danish National Patient Registry (discharge diagnoses coded according to the International Classification of Diseases (ICD)-10 since 1994), and 3) the Danish National Causes of Death Registry (date of death and underlying causes of death from death certificates). All registries have been validated previously [