Emergency
Wells score calculator for deep vein thrombosis
Calculate the Wells score for deep vein thrombosis to stratify pre-test probability before D-dimer and compression ultrasound. For use by licensed clinicians.
Wells score for DVT
0points
Low probability. The score stratifies pre-test probability — it does not rule DVT in or out on its own. It is combined with D-dimer and compression ultrasound according to your local pathway, and is not validated in pregnancy or in patients already anticoagulated.
For use by licensed clinicians as a calculation aid only. It does not account for the individual patient context, and it does not replace clinical judgement or your local protocol. Verify any value before it informs a dose or a decision.
Equation used
One point for each of: active cancer; paralysis or recent immobilisation; bedridden ≥3 days or major surgery within 12 weeks; localised tenderness along the deep venous system; entire leg swollen; calf swelling >3 cm; pitting oedema in the symptomatic leg; non-varicose collateral superficial veins; previously documented DVT. Minus two points if an alternative diagnosis is at least as likely.
Source
Wells PS et al., The Lancet, 1997; revised 2003
A pre-test probability tool, not a diagnostic one. It is not validated in pregnancy or in patients already on anticoagulation.
Common questions
What Wells score rules out DVT?
No score rules out DVT alone. A score of 0 or below is low probability, and it is the combination of low probability with a negative high-sensitivity D-dimer that permits DVT to be excluded without imaging under most pathways.
Can the Wells DVT score be used in pregnancy?
No. It was not derived or validated in pregnancy, where leg swelling is common and D-dimer rises physiologically. Use a pregnancy-specific pathway such as LEFt.