Hematology
Time in Therapeutic Range (TTR) & SAMe-TT₂R₂ Warfarin vs DOAC Score
Evaluates INR anticoagulation quality (Rosendaal TTR target ≥ 70%) and SAMe-TT₂R₂ score to guide DOAC transition.
%20%26%20SAMe-TT%E2%82%82R%E2%82%82%20Warfarin%20vs%20DOAC%20Score&category=Hematology)
Enlarge
Parameters
Time in Therapeutic Range (TTR) & SAMe-TT₂R₂ Warfarin vs DOAC Score Result
--
Formula
SAMe-TT₂R₂ = Sex (F=1) + Age (<60=1) + Medical Comorbidities (≥2=1) + Treatment (Amiodarone=1) + Tobacco (2) + Race (Non-Caucasian=2)
TTR ≥ 70% defines international gold-standard anticoagulation quality.Clinical Pearls
Prevents preventable thromboembolic strokes and fatal hemorrhages by identifying patients failing vitamin K antagonist therapy who will benefit from modern DOACs.
Limitations
TTR requires at least 3 to 6 months of consecutive INR records to calculate reliably via linear interpolation.