A large-scale Danish population-based preventive programme ` Check your health ' was developed based on available evidence of screening and successive accepted treatment , prevention for diseases and health promotion , and is closely aligned with the current health care system.The objective of the ` Check your health ' [ CORE ] trial is to investigate effectiveness on health outcomes of a preventive health check offered at a population-level to all individuals aged 30-49 years , and to establish the cost-effectiveness .