Wells’ score calculator

Wells’ score calculator: Pre-test probability of deep vein thrombosis (DVT)

Choose yes OR no among these as per clinical situation !!

1. Active cancer (cancer treatment within last 6 months, or palliation for cancer)?

2. Lower limb trauma or surgery or immobilisation in a plaster cast ?

3. Bedridden for more than three days or surgery within the last four week ?

4. Localised tenderness along deep venous system/Tenderness along line of femoral or popliteal veins (NOT just calf tenderness)?

5. Calf diameter 3 or more centimeters greater than unaffected side (Measure calf diameter 10cm below tibial tuberosity) ?

6. Entire leg swollen?

7. Unilateral pitting edema?

8. Dilated collateral superficial veins (non-varicose) ?

9. Past Hx of confirmed DVT?

10. Is an alternative diagnosis as least as likely as a deep vein thrombosis?


Wells’ score Risk of DVT on ultrasound
Wells’ score of -2 to 0 Low risk of DVT on ultrasound (3%)
Wells’ score of 1 or 2 Intermediate risk of DVT (17%)
Wells’ score of 3 or More High risk of DVT (75%)

As published originally Patients with a Wells’ score of -2 to 0 were at low risk of DVT on ultrasound (3%), those with a score of 1 or 2 were at intermediate risk (17%), and those with a score of 3 or more at high risk (75%). Ref: Wells PS, Anderson DR, Bormanis J, et. al. Value of assessment of pretest probability of deep-vein thrombosis in clinical management. Lancet. 1997 Dec 20-27;350(9094):1795-8.

Incorporating Value of D-dimer the scoring system was modified.

Evaluation of D-dimer in the diagnosis of suspected deep-vein thrombosis. Wells PS et al. N Engl J Med. 2003 Sep 25;349(13):1227-35.

Patients were considered at low risk of DVT if the Wells’ score was < 2 and D-dimmer was negative.