Study to Describe Risk of Bleeding in Patients Depending on the Different Anticoagulant Therapy They Are on for Atrial Fibrillation (AF)

Inclusion Criteria: * Diagnosis of atrial fibrillation at or prior to index (the initiation of treatment) * Incident prescription of an oral anticoagulant (index date) * Patients with at least one year of computerized data prior to index date Exclusion Criteria: * Patients identified with a diagnosis of mechanical heart valve replacement or mitral stenosis identified at any point in the pre-index period in either CPRD by Read codes or in HES as ICD-10/OPCS codes * Patients with indication of venous thromboembolism (pulmonary embolism or deep vein thrombosis) identified in in either CPRD by Read codes or HES by ICD-10/OPCS codes within 3 months prior to index Other protocol defined inclusion/exclusion criteria could apply