HERDOO2 (women with unprovoked VTE)
HERDOO2 rule (Rodger 2017; women only): post-thrombotic leg signs, D-dimer >= 250 ug/L on anticoagulation, BMI >= 30, age >= 65 (1 each); 0-1 can safely discontinue anticoagulation, >= 2 continue.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Post-thrombotic leg signs (hyperpigmentation, edema, redness)
- Yes
- D-dimer >= 250 ug/L while on anticoagulation
- Yes
- BMI >= 30 kg/m^2
- No
- Age >= 65 years
- No
Result: HERDOO2 2 of 4 (women): continue anticoagulation per Rodger 2017 (>=2 band).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- 0-1
- Low risk; safe to discontinue anticoagulation per Rodger 2017 (women with unprovoked VTE).
- >=2
- Continue anticoagulation per Rodger 2017.
What you enter
- Post-thrombotic leg signs (hyperpigmentation, edema, redness) (1)
- D-dimer >= 250 ug/L while on anticoagulation (1)
- BMI >= 30 kg/m^2 (1)
- Age >= 65 years (1)
How this is calculated
Rodger MA, Le Gal G, Anderson DR, et al. Validating the HERDOO2 rule to guide treatment duration for women with unprovoked venous thrombosis: multinational prospective cohort management study. BMJ. 2017;356:j1065. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.