SAMe-TT2R2 (VKA Anticoagulation Control)
SAMe-TT2R2 score predicting how well a patient will maintain therapeutic INR on warfarin; > 2 suggests a DOAC or extra INR support.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Tobacco use within 2 years
- Yes
Result: SAMe-TT2R2 2 — poorer VKA control predicted.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Cut
- 0–1 predicts good INR control on a VKA; ≥ 2 predicts poorer control (favoring a DOAC or closer monitoring).
What you enter
- Female sex
- Age < 60 years
- Medical history (≥ 2 comorbidities)
- Interacting drugs (e.g. amiodarone)
- Tobacco use within 2 years (2)
- Non-white race (2)
How this is calculated
- Points
- Sex F +1, age < 60 +1, ≥ 2 comorbidities +1, interacting drugs +1, tobacco +2, non-white race +2.
Apostolakis S, Sullivan RM, Olshansky B, Lip GYH. Factors affecting quality of anticoagulation control among patients with atrial fibrillation on warfarin: the SAMe-TT2R2 score. Chest. 2013;144(5):1555-1563. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.