OBJECTIVE: To develop a method to evaluate routine management practices concerning lipid-lowering treatment in patients with ischaemic heart disease (IHD) in a large geographic area. DESIGN: A register-based study linking information on IHD with cholesterol levels and prescriptions on lipid-lowering medications by personal registration number. Plasma cholesterol levels were collected from the electronic laboratory information system (LIS), and information on IHD from the Danish National Hospital Register (LPR). The extent of treatment was evaluated by information on prescriptions on lipid-lowering medications from the Danish National Health Service. SETTING: Evaluates treatment in both hospitals and primary care. SUBJECTS: Patients with IHD. RESULTS: In total 3477 patients