Wells Score for Deep Vein Thrombosis

Wells et al: Lancet 1997; 350: 1795-1798

active cancer (on-going treatment or diagnosed within 6 months or palliative care)- score 1
paresis, paralysis or recent plaster cast immobilisation of lower extremity- score 1
recently bedridden for more than 3 days and/or major surgery within 4 weeks- score 1
localised tenderness over distribution of deep veins- score1
entire leg swollen- score1
calf swelling more than 3 cm compared with asymptomatic side, measured at 10 cm below tibial tubercle- score 1
pitting oedema (greater in symptomatic leg)- score 1
collateral superficial veins (non-varicose)- score 1
alternative diagnosis as likely or greater than that of DVT- score -2

In patients with symptoms in both legs, the most symptomatic leg is used.
score 0 or less- low risk  (3% probability DVT)
score 1 or 2- moderate risk  (17% probability DVT)
score 3 or more- high risk  (75% probability DVT)