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Wells Score for PE

The most-used PE pretest probability score — and the gate every other PE tool is built on top of.

Low risk · PE unlikely
Wells <2 · ~1.3% PE prevalence
Check D-dimer — if negative, PE excluded
This is the PERC population: if all 8 PERC criteria are also negative, PE is excluded without a D-dimer
0pts
Clinical signs and symptoms of DVT (leg swelling, pain on palpation of deep veins)
PE is the #1 diagnosis, or equally likely
Heart rate >100 bpm
Immobilization ≥3 days, or surgery within the past 4 weeks
Previous PE or DVT
Hemoptysis
Malignancy (treatment within 6 months, or palliative)
Wells PS, et al. 1998 · revised 2000 · Note the 1.5-point increments — totals are not integers. Both models shown: three-tier (<2 / 2–6 / >6) and two-tier (unlikely ≤4 / likely >4). A normal heart rate is NOT reassuring — up to 40% of confirmed PEs present with HR <100.