Table 1. The Wells pre-test probability score.⁴

Wells Score
Criterion	Points Value
Clinical signs of DVT	+3.0
Alternative Dx less probable than PE	+3.0
Heart rate > 100/min.	+1.5
Immobilization or surgery <4 wk. ago	+1.5
Previous DVT or PE	+1.5
Hemoptysis	+1.0
Cancer	+1.0

• Total points score: <2 low probability with 2% risk of PE
• Total points score: 2-6 moderate probability with 19% risk of PE
• Total points score: >6 high probability with 50 % risk of PE