UKMLA PLAB AMC USMLE Prometric MCQ

Question Number 0173
Question:
A 45 year old male with a history of a prosthetic mechanical heart valve is on long term treatment with coumadin receiving 5 mg a day. He visits the coagulation clinic regularly for assessment. Coumadin effectiveness is most appropriately assessed with

a) Platelet count
b) Clot retraction
c) Tourniquet test
d) Bleeding time
e) Prothrombin time (PT)