The new generation of antithrombotic agents, known as Direct Oral Anticoagulants (DOACs), act on a single factor within the coagulation cascade. Although the monitoring of therapy is not necessary for DOACs, measuring the anticoagulant effect is useful in many clinical situations, especially pre-operative evaluation [1]. Specific tests, which quantify the drug indirectly, and nonspecific tests, which are altered by DOACs, are used to evaluate the anticoagulant effect of DOACs. The aim of this study is to assess the responsiveness of the specific and non-specific assays used at IRCCS Policlinico San Donato to low DOAC concentrations and to compare the responsiveness between calibrators and patients with nonspecific assays.
