My startup facilitates at home testing of PT&#x2F;INR levels (for coumadin&#x2F;warfarin patients). In general, yes, INR levels stabilize, medicare won&#x27;t pay for at home testing until the patient has been on warfarin for 90 days. However, it is surprising how many critically high or low results we get in an average week.<p>Studies [1] show that weekly INR testing results in a 55% reduction in strokes, 35% reduction in major bleeds and 39% reduction in deaths.<p>[1] Henagen C. et al. Lancet 2006; 367:404-11