Wells' DVT Criteria Score
Calculate Wells' clinical prediction score for deep vein thrombosis (DVT) probability to guide imaging and D-dimer testing strategy.
Results
What is it?
For educational and clinical reference only. Not a substitute for professional medical judgment. Always verify with current clinical guidelines and consult qualified healthcare providers. The Wells' DVT score is a validated clinical prediction rule for estimating the pre-test probability of deep vein thrombosis. It combines 9 positive criteria and 1 negative criterion. Score =0: Low probability (~5% DVT prevalence). Score 1�2: Moderate (~17%). Score =3: High (~53%).
How to use
Check all clinical criteria present in the patient. The score and risk category (Low/Moderate/High) are computed. Use alongside D-dimer testing: low probability + negative D-dimer effectively rules out DVT without imaging in most guidelines.
Example scenario
A patient with entire leg swelling (1), pitting edema (1), and previous DVT (1) but an alternative diagnosis is equally likely (-2): Score = 3-2 = 1 ? Moderate probability. Proceed with D-dimer and/or compression ultrasound.
Pro tip
Wells' score has been validated in outpatient and ED settings. In high-probability patients, skip D-dimer and proceed directly to compression ultrasound. The YEARS algorithm and PEGeD trial have modified DVT/PE diagnostic pathways � ensure you apply the protocol relevant to your institution.