Cardiovascular & clot risk

Wells score for DVT

Two-level lower-extremity DVT clinical probability.

Intended population: Adults with suspected lower-extremity DVT; general nonpregnant pathway.

A low score does not exclude a clot. Follow a validated diagnostic pathway and local testing guidance.
Do not delay emergency assessment for instability. This general adult version is not a pregnancy/postpartum pathway or a rule for patients already receiving therapeutic anticoagulation.
For suspected lower-extremity DVT, not upper-extremity thrombosis.

Adult with suspected lower-limb DVT; not pregnant/postpartum or already therapeutically anticoagulated

Active cancer: current treatment, treatment within 6 months, or palliative

Lower-limb paralysis, paresis, or recent cast immobilization

Bedridden for at least 3 days, or major surgery within 12 weeks with general/regional anesthesia

Tenderness along the deep venous system

Entire leg swollen

Calf at least 3 cm larger than the other side (measured 10 cm below tibial tuberosity)

Pitting edema limited to the symptomatic leg

Nonvaricose collateral superficial veins

Previously documented DVT

An alternative diagnosis is at least as likely as DVT

Sources and scoring references

NICE NG158: venous thromboembolic disease ↗

Implementation references reviewed October 28, 2026. Verify applicability and unusual or treatment-changing results against the linked references and local guidance.