ToolsCalculators
IMPROVEDD Risk Score for Venous Thromboembolism (VTE)
Adds D-dimer to the IMPROVE score to refine 3-month VTE risk in hospitalized medical patients.
IMPROVEDD Risk Score for Venous Thromboembolism (VTE)
Previous VTE
Known thrombophilia
Current lower-limb paralysis
Current active cancer
Immobilized ≥7 days (current admission)
ICU or CCU stay
Age >60 years
D-dimer ≥2× the upper limit of normal
Result0 points
Adding D-dimer to the IMPROVE score improves discrimination of 3-month VTE risk; higher scores indicate progressively higher risk.
When to use
- Refining VTE risk stratification in hospitalized medical patients when a baseline D-dimer is available.
- Informing the decision to start or intensify pharmacologic VTE prophylaxis.
Formula
IMPROVE score (previous VTE +3, known thrombophilia +2, current lower-limb paralysis +2, current cancer +2, immobilization ≥7 days +1, ICU/CCU stay +1, age >60 years +1) plus 2 points if D-dimer ≥2× the upper limit of normal. Range 0-14.
Pearls and pitfalls
- Incorporating D-dimer improved risk discrimination (higher c-statistic) compared with the original IMPROVE score alone.