herdoo2_rule: HERDOO2 Rule for Discontinuing Anticoagulation in Unprovoked...

In cliot: Clinical Indices and Outcomes Tools

HERDOO2 Rule for Discontinuing Anticoagulation in Unprovoked VTE

Description

Calculates the HERDOO2 score to identify women with unprovoked venous thromboembolism (VTE) who have a low risk of recurrence and can safely discontinue anticoagulation. Men are considered high risk regardless of the score and should generally continue anticoagulation.

Usage

herdoo2_rule(post_thrombotic_signs, d_dimer_ge_250, bmi_ge_30, age_ge_65)

Arguments

post_thrombotic_signs	Numeric (0 or 1). Presence of post-thrombotic signs (Hyperpigmentation, Edema, or Redness in either leg). (1 = Yes, +1 point).
d_dimer_ge_250	Numeric (0 or 1). D-dimer level >= 250 µg/L on anticoagulation. (1 = Yes, +1 point).
bmi_ge_30	Numeric (0 or 1). Body Mass Index >= 30 kg/m^2. (1 = Yes, +1 point).
age_ge_65	Numeric (0 or 1). Patient age >= 65 years. (1 = Yes, +1 point).

Value

A list containing:

HERDOO2_Score	The calculated score (Range 0-4).
Risk_Category	"Low Risk" (Score 0-1) or "High Risk" (Score >= 2).
Recommendation	Guidance on continuing vs. stopping anticoagulation.

References

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. doi:10.1136/bmj.j1065

Examples

# Example 1: Low Risk Woman
# No PTS signs, D-dimer 200, BMI 25, Age 50
# Score = 0
herdoo2_rule(0, 0, 0, 0)

# Example 2: High Risk Woman
# Edema present (+1), Age 70 (+1)
# Score = 2
herdoo2_rule(1, 0, 0, 1)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.