5.4.2 Randomization After patients sign informed consent they will be randomized to either Fiix-PT (test method, Fiix INR) or PT (PT-INR based on Quick PT method as a control method). Randomization will be done manually at time of signing the informed consent, ie the participants will draw a labeled color card with an assigned study number (CRF number) which will randomize them to either the test group or the control group. The coagulation laboratory (supervised by BRG) will maintain a list of study participants during the study. They will be responsible for randomization (color assignment) following the signing of informed consent. Following randomization, each patient will be assigned a study participant number. The laboratory will based on this participant number and color code as appropriate direct each patient´s sample to test A (Fiix-INR) or test B (PT-INR) which will be measured in the Landspitali coagulation laboratory using the STA-R instrument (Stago).