Wells Score Calculator for DVT
Assess the clinical probability of deep vein thrombosis (DVT) using the Wells Score. This validated scoring system uses 10 clinical criteria to classify patients into low, moderate, or high probability categories and guide the diagnostic workup.
The Wells Score for DVT was developed by Dr. Philip Wells and colleagues in 1997 and has become the standard clinical prediction tool for assessing DVT probability before ordering diagnostic tests. It helps clinicians decide whether to start with a D-dimer blood test or proceed directly to ultrasound imaging.
Scoring criteria (each +1 point unless noted):
- Active cancer (treatment within 6 months or palliative)
- Paralysis, paresis, or recent plaster immobilization of the leg
- Bedridden for >3 days or major surgery within 12 weeks
- Localized tenderness along the deep venous system
- Entire leg swollen
- Calf swelling >3 cm larger than the asymptomatic side (measured 10 cm below the tibial tuberosity)
- Pitting edema confined to the symptomatic leg
- Collateral superficial veins (non-varicose)
- Previously documented DVT (+1)
- Alternative diagnosis at least as likely as DVT (-2 points)
3-tier interpretation:
- Score 0 or less: Low probability (~5% have DVT)
- Score 1-2: Moderate probability (~17% have DVT)
- Score 3+: High probability (~53% have DVT)
2-tier (modified) interpretation:
- Score 1 or less: DVT unlikely -- proceed with D-dimer
- Score 2+: DVT likely -- proceed with ultrasound
The 2-tier model is now more widely used in clinical practice because it creates a cleaner decision pathway: "unlikely" patients get a D-dimer first (if negative, DVT is ruled out), while "likely" patients go straight to imaging.
This tool is for educational purposes only and should not replace professional medical advice.