The mnemonic
1972
What each word stands for
- 1Factor X (10)
- 9Factor IX (9)
- 7Factor VII (7)
- 2Factor II (2)
Why it matters clinically
Explains why warfarin prolongs PT and why INR is monitored.
Where it stops being reliable
Leaves out proteins C and S, which are also vitamin K dependent and explain early skin necrosis.
Teaching aid, still awaiting independent review. Confirm facts in a standard source.