Protocol: Experimental subjects will be selected from patients attending the Coagulation Clinic. Patients will be seen in the clinic and receive their usual follow-up care. After obtaining informed consent, the participants' coagulation status will be assessed with the new sensor. Patients on warfarin medications will have a venous blood sample obtained (5 ml) for determination of INR. Patients receiving NOACs will have a venous blood sample obtained (5 ml) for determination of Factor Xa activity. At a later date, the coagulation status of the patients as assessed by the new sensor will be compared to the coagulation status as assessed by the standard laboratory methods.