Study population
The study was conducted as a randomized trial embedded in DNHS-2021, where the population was based on six mutually exclusive random subsamples among the adult (aged 16 years or older) Danish population: one in each of the five Danish administrative regions, and one national sample. The samples were drawn from the adult population in Denmark (including institutionalized people) using the Danish Civil Registration System which contains basic information on all people who are currently residing in Denmark [