Wells' score — DVT
Pre-test probability of deep vein thrombosis.
What it is for
Suspected DVT. Score ≥ 2 → DVT likely (USS); < 2 → D-dimer.
Use the working calculator
The working Wells' score — DVT calculator is on our calculators page. It is free and needs no account. Enter the values and it shows the result with the reading that goes with it.
The calculators are free. The trial opens the protocols and pathways they link to.What you enter
The calculator asks for 10 items.
- Active cancer (within 6 months / palliative) (1 point)
- Paralysis, paresis, or recent leg plaster (1 point)
- Bedridden ≥ 3 days OR major surgery within 12 weeks (1 point)
- Localised tenderness along deep venous system (1 point)
- Whole leg swollen (1 point)
- Calf swelling > 3 cm vs other side (1 point)
- Pitting oedema (greater in symptomatic leg) (1 point)
- Collateral non-varicose superficial veins (1 point)
- Previously documented DVT (1 point)
- Alternative diagnosis at least as likely (-2 points)Subtracts 2 — e.g. cellulitis, Baker cyst.
How the result is read
The result is shown as Wells' (DVT) score, out of a maximum of 9.
The calculator reads each total as follows. Where a single answer changes the reading (for example sex, age or one extreme value), the working calculator says so.
| Total | Band | What the calculator says |
|---|---|---|
| 0 to 1 | DVT unlikely | D-dimer (high-sensitivity). If positive → USS within 4 h. If negative → DVT excluded. NICE NG158. |
| 2 to 9 | DVT likely | NICE NG158: DVT likely band — see the DVT protocol and NICE NG158 for imaging and interim anticoagulation. NICE NG158 pathway. |
Sources
These are the sources the calculator cites. Check the current version before relying on a threshold.
Related
For qualified clinicians. A score supports a clinical decision and does not make it: check the inputs, read the cited source, and use the tools in your clinical system for patient care where one is provided.