Heart and clots

Wells score for DVT

How likely a deep vein thrombosis is, before any test.

TellClots form when blood slows, the vessel wall is hurt, or the blood turns sticky. Each point is one of those three, seen at the bedside.

Active cancer (treated in the last 6 months, or palliative)+1
Paralysis, paresis, or a recent cast on the leg+1
Bedridden 3 or more days, or major surgery in the last 12 weeks+1
Tenderness along the deep veins+1
Entire leg swollen+1
Calf over 3 cm bigger than the other side, measured 10 cm below the tibial tuberosity+1
Pitting edema only in the painful leg+1
Collateral surface veins (not varicose)+1
A DVT documented before+1
Another diagnosis is at least as likely−2

0 points

DVT unlikely

Check a high-sensitivity D-dimer. Negative ends the workup. Positive means an ultrasound.

Nothing you enter is saved or sent. US units. Education, not medical advice.

When I reach for it

A swollen or painful leg, before I order a D-dimer or an ultrasound.

Where it misleads

It was built in outpatients. In hospitalized patients, in pregnancy, or with an old clot in the same leg it is less reliable. The minus 2 depends on how honestly you weigh the other diagnosis.

How it is built

One point each for cancer, paralysis or a recent cast, bed rest or recent surgery, tenderness along the deep veins, a whole swollen leg, a calf 3 cm bigger, pitting edema in that leg, collateral surface veins, and a prior DVT. Minus 2 if another diagnosis is at least as likely. 2 or more is likely.

Built on

Wells PS et al., NEJM 2003; ASH 2018 guideline on VTE diagnosis.

More in Heart and clots

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Wells score for PE
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Patient-facing content is general health education, not medical advice. Reading it does not establish a doctor–patient relationship. No protected health information is published; any patient examples are composite and fictionalized. TRENCHWORK is independent and not affiliated with any payer, hospital system, or vendor.