Pretest clinical probability scoring for DVT: the Wells score
In patients with symptoms in both legs, use the more symptomatic leg.
Active cancer (treatment within last 6 months or palliative)
Paralysis, paresis, or recent plaster immobilisation of leg
Major surgery or recently bedridden for >3 days in last 4 weeks
Local tenderness along distribution of deep venous system
Entire leg swollen
Calf swelling >3cm compared to asymptomatic leg (measured 10cm below the tibial tuberosity)
Collateral superficial veins (non-varicose)
Alternative diagnosis as likely or more likely than that of DVT
- ≥3 points: High probability-treat as suspected DVT or perform compression US.
- 1-2 points: Intermediate probability-treat as suspected DVT and perform compression US.
- ≤0 points: Low probability of DVT-perform D-dimer test. If positive D-dimer then treat as suspected DVT and perform compression US. If negative D-dimer, DVT reliably excluded.
Adapted Well’s score for Pulmonary Embolism
Clinical signs and symptoms of Deep Vein Thrombosis
PE is most likely diagnosis
Tachycardia (>100 bpm)
Immobilisation or surgery in the previous 4 weeks
Previously diagnosed DVT or PE
Malignancy (treatment within last 6 months or palliative)
- ≥7 points: High probability
- 2.0-6.0 points: Intermediate probability
- 0-1 points: Low probability