Dosing and monitoring

Why?

• Dosing using a computer program reaches a therapeutic and stable INR faster than using physicians' predictions (on average 4 days) ^a
• Patients leave hospital a week sooner, and are more likely to have a therapeutic INR after 2 weeks. ^a

Computer dosing of warfarin increases the chance of a therapeutic INR after 2 weeks

Patient	Treatment	Comparison	Outcome	CER	RRR (95% CI)	NNT (95% CI)
venous thromboembolism, atrial fibrillation a	computer dosing of warfarin	physician dosing of warfarin	therapeutic PT at 10-14 days	31%	-135% (-299% to -38%)	2 (2 to 5)

• Guideline-based consultation reduces anticoagulant-related bleeding and venous thromboembolism. ^a

Guideline-based consultation reduces bleeding and venous thromboembolism

Patient	Treatment	Comparison	Outcome	CER	RRR (95% CI)	NNT (95% CI)
starting anticoagulation and considered moderate or high risk for bleeding a	guideline-based consultation	usual care	any bleeding at 3 months	31%	58% (2% to 82%)	6 (3 to 45)
			new or recurrent PE or DVT at 3 months	16%	73% (-17% to 94%)	8 (4 to 160)