Evaluating LumiraDx INR Test Accuracy in Patients Taking Phenprocoumon Anticoagulant.

This study is to evaluate the INR levels in patients taking phenprocoumon using the LumiraDx Point of Care INR test and comparing the results to the laboratory reference method , the ACL Elite Pro. Comparison will also be made with the Roche Coaguchek point of care INR test (point of care reference method). Performance will be demonstrated across a subject population of adult males and females in receipt of Phenprocoumon VKA therapy. This population is representative of the indications for use of the CE marked product. Operators will be trained clinical site staff. Venous plasma and capillary whole blood samples will be obtained from each subject in order to assess accuracy of the the LumiraDx Platform when compared to the reference devices (ACL Elite and Coaguchek Pro).

Inclusion Criteria: * Persons \>18 years of age * Willing and able to provide written informed consent and comply with study procedures * Currently prescribed Phenprocoumon VKA Therapy * Deemed medically appropriate for study participation by the Investigator Exclusion Criteria: * Subject has previously participated in this part of the study * Subject is within 4 weeks of first prescription of Phenprocoumon * Subject is taking a DOAC, or non-Phenprocoumon VKA therapy * Confirmed or suspected pregnancy * Vulnerable populations deemed inappropriate for study by the Investigator * Deemed medically inappropriate for study by the Investigator (i.e. patients with a known inherited \[e.g. haemophilia or von Willebrand's disease\] or acquired \[e.g. liver cirrhosis\] condition likely to be associated with a coagulopathy; or patients receiving non-VKA anticoagulant medications)