Wells Score (Pulmonary Embolism)

Select each applicable criterion and enter heart rate to calculate the Wells score for pulmonary embolism.

Clinical signs of DVT (3 points)

Includes leg swelling and pain with palpation of the deep veins.

PE more likely than alternative diagnosis (3 points)

Clinical judgement that PE is the most likely explanation.

Heart rate (beats/min)

Adds 1.5 points if heart rate > 100 bpm.

Immobilisation ≥3 days or surgery within 4 weeks (1.5 points)

Includes casting or general anesthesia.

Previous DVT or PE (1.5 points)

Hemoptysis (1 point)

Malignancy (1 point)

On treatment, treated within 6 months, or palliative.

Wells score

0.0

Probability category

Low probability (<2)

If PERC-negative, no further testing is required. Otherwise, perform D-dimer testing before imaging.

How to Use This Calculator

Gather clinical data

Assess for DVT signs, recent surgery, immobilisation, prior VTE, hemoptysis, cancer, and heart rate.

Determine pretest probability

Use the Wells score to stratify patients into low, intermediate, or high probability of pulmonary embolism.

Select next diagnostic step

Choose D-dimer testing, imaging, or treatment initiation based on the calculated probability and clinical judgement.

Formula

Wells score = 3 points (clinical DVT) + 3 points (PE more likely than alternate diagnosis) + 1.5 points (heart rate >100 bpm) + 1.5 points (immobilisation/surgery) + 1.5 points (previous DVT/PE) + 1 point (hemoptysis) + 1 point (malignancy). Probability: <2 low, 2–6 intermediate, >6 high.

Full Description

The Wells score for pulmonary embolism is a clinical prediction rule validated across multiple populations. It stratifies patients to guide subsequent testing such as D-dimer or CT pulmonary angiography. Combining Wells with PERC and age-adjusted D-dimer thresholds reduces unnecessary imaging while maintaining diagnostic safety.

Frequently Asked Questions

Should I use the simplified (two-tier) Wells model?

Yes, many guidelines use a cutoff of 4.0 to separate “PE unlikely” from “PE likely.” This calculator provides the traditional three-tier system.

Can I apply Wells in pregnant patients?

Wells was not validated in pregnancy; use pregnancy-adapted algorithms and consult obstetric guidance.

Do I need imaging if the score is low and D-dimer negative?

No. A low Wells score plus negative D-dimer safely excludes PE in most situations.

How does Wells integrate with YEARS or PEGeD criteria?

These newer algorithms modify D-dimer thresholds; select the approach endorsed by your institution for consistency.