After the pivotal phase 3 trials on venous thromboembolism (VTE) treatment with non-vitamin K antagonist oral anticoagulants (NOACs) had been performed some 10 years ago, these drugs have now become the standard anticoagulant treatment of VTE. While randomized controlled trials (RCT) carefully select patients to allow homogeneous comparisons between the randomized groups, real world evidence (RWE) is required from a much larger patient population with a high variation of clinical characteristics.