Score bleeding risk on anticoagulation with the published HAS-BLED items and their published annual bleeding rates.
Result
How to use this tool
Choose yes or no for hypertension, organ function, stroke, bleeding, INR stability, age, drugs and alcohol.
The score runs 0–9; 0–1 is low, 2 moderate, 3+ high in this tool’s bands.
The matching annual bleeding rate from the original cohort is shown.
Raise blood pressure, alcohol, interacting drugs and INR control with the prescriber.
Formula & worked example
No HAS-BLED factors scores 0 / 9, with a published rate of 1.13 bleeds per 100 patient-years. Hypertension, prior stroke and age over 65 score 3 / 9, with a published rate of 3.74 per 100 patient-years.
Limitations — read this before you rely on it
Screening aid based on the original HAS-BLED cohort; individual risk varies and anticoagulation decisions need a clinician. This tool is for education only and is not medical advice. Talk to a clinician about any result that worries you, and never change treatment because of a calculator result.
Frequently asked questions
Hypertension, Abnormal renal/liver function, Stroke, Bleeding history, Labile INR, Elderly, Drugs/alcohol — one point each, nine points maximum.
No. Guidelines use it to flag modifiable risks and closer review, not as an automatic reason to stop anticoagulation.
An INR that is often out of range or unstable over time, rather than a single out-of-range reading.
Per 100 patient-years: 0: 1.13, 1: 1.02, 2: 1.88, 3: 3.74, 4: 8.70, 5+: 12.5 (Pisters et al., 2010).
No. It is a screening aid for discussion with the prescribing clinician, who weighs stroke risk against bleeding risk.