Table 2.

Wells score for PE clinical pretest probability

	Number of points	Proportion of patients	Prevalence of PE
Variables
Clinically suspected DVT	3
Alternative diagnosis is less likely than PE	3
Heart rate >100 beats/min	1.5
Immobilization or surgery in previous 4-wk period	1.5
History of VTE	1.5
Hemoptysis	1
Malignancy or treatment of it in previous 6-mo period	1
Score interpretation
High probability*	≥6.5	10%	60%
Moderate probability*	4.5-6.0	30%	25%
Low probability†	≤4.0	60%	5%

^*A score of ≥4.5 (moderate and high probability groups combined) has been termed “PE likely.” This group makes up ∼40% of patients and has a prevalence of PE of ∼33%.

^†Is also termed “PE unlikely.” In the original derivation of the Wells PE model, patients were required to have a score of ≤1.5 to be categorized as low probability, but a score of ≤4 has subsequently been used for low probability.^8,9