Modified IMPROVE VTE risk score
| VTE risk factor | VTE risk score |
| Previous VTE | 3 |
| Known thrombophilia | 2 |
| Current lower limb paralysis or paresis | 2 |
| History of cancer | 2 |
| ICU/CCU stay | 1 |
| Complete immobilisation ≥1 day | 1 |
| Age ≥60 years | 1 |
CCU, critical care units; ICU, intensive care unit; IMPROVE, International Medical Prevention Registry on Venous Thromboembolism; VTE, venous thromboembolism.