How is the Wells PE score calculated?

Seven clinical criteria are scored with variable point weights: 3.0 points each for clinical signs of DVT and PE being the most likely diagnosis; 1.5 points each for heart rate > 100, recent immobilization/surgery, and prior DVT/PE; and 1.0 point each for hemoptysis and active malignancy. Points are summed to yield a total score.

What is low, moderate, and high probability?

A Wells score below 2 is Low probability (~3% chance of PE). A score of 2–6 is Moderate probability (~20% chance). A score above 6 is High probability (~40–67% chance). These cutoffs are from the original Wells 3-tier model.

When should I order CT-PA directly without a D-dimer?

CT pulmonary angiography is generally recommended directly for High probability patients (score > 6) because a positive D-dimer in that group adds no information, and CT is needed regardless. In Moderate cases with a positive D-dimer, CT-PA is also indicated.

What does "PE is the #1 diagnosis or equally likely" mean?

This criterion is positive when the treating clinician judges PE to be the most probable explanation for the presentation, or at least as likely as any other diagnosis being considered. It carries the highest point value (3.0) because it reflects gestalt clinical suspicion.

How does this differ from the simplified Wells score?

The original (this tool) uses weighted points (1.0, 1.5, 3.0) and produces a 3-tier Low/Moderate/High classification. The simplified model assigns 1 point to each criterion and produces a 2-tier Unlikely (0 points) vs. Likely (≥1 point) result. Both models have similar diagnostic accuracy in validation studies.

Can this tool be used in pregnant patients?

The Wells criteria were not validated specifically in pregnant patients. Suspected PE in pregnancy requires specialist guidance, a modified imaging workup, and pregnancy-specific D-dimer thresholds. Do not apply this score alone to pregnant patients.

Is this a substitute for clinical judgment?

No. This tool is intended for educational and clinical decision-support purposes only. All diagnostic and treatment decisions must be made by a licensed clinician with full knowledge of the patient's history, examination, and test results.

Wells PE Score (Pulmonary Embolism)

Score all seven Wells criteria with point-by-point breakdown to classify PE pre-test probability as low, moderate, or high.

Clinical Criteria

Check all that apply

Each criterion shows its point value and clinical definition.

Clinical signs and symptoms of DVT +3

Objective leg swelling, or pain with palpation along a deep vein distribution.

PE is the #1 diagnosis, or equally likely +3

Clinician judges PE as the most probable cause, or at least as likely as any alternative.

Heart rate > 100 bpm +1.5

Tachycardia documented at time of evaluation.

Immobilization ≥ 3 days OR surgery in past 4 weeks +1.5

Bed rest for ≥3 consecutive days, or any surgical procedure within 4 weeks.

Previous objectively diagnosed DVT or PE +1.5

Prior venous thromboembolism confirmed by objective testing (imaging or autopsy).

Hemoptysis +1

Patient is coughing up blood or blood-stained sputum.

Malignancy (treatment within 6 months or palliative) +1

Active cancer receiving treatment within the last 6 months, or on palliative care.

Point Breakdown

Criterion	Points
Total	0

Wells Score

0 Total Points

0 2 6 12.5

Low Moderate High

Select criteria to score

Recommended Next Step

Check criteria on the left to see the recommended workup.

Score Reference

Low Probability < 2 pts — ~3%

Moderate Probability 2 – 6 pts — ~20%

High Probability > 6 pts — ~40–67%

For educational and clinical reference only. All diagnostic decisions must be made by a licensed clinician.

Summary

The Wells PE Score calculator applies the original Wells criteria scoring system to estimate the pre-test probability of pulmonary embolism (PE). It assigns weighted points (1.0, 1.5, or 3.0) to seven clinical variables and stratifies patients into Low (< 2), Moderate (2–6), or High (> 6) probability tiers. Each criterion includes its clinical rationale to support bedside teaching and documentation. The tool also displays a per-criterion point breakdown so clinicians can audit the score at a glance.

How it works

Read the clinical definition shown beneath each of the seven criteria.
Check every criterion that is present in the patient being evaluated.
Points are summed automatically and displayed in the score panel on the right.
The risk tier (Low / Moderate / High) updates in real time based on the total.
Review the recommended next diagnostic step shown under the risk badge.
Click Reset to clear all checkboxes and start a new evaluation.

Use cases

Stratify PE pre-test probability in the emergency department or inpatient ward.
Decide whether D-dimer testing is sufficient or CT-PA is required.
Teach Wells criteria point values to medical students and residents.
Document objective risk stratification in clinical notes.
Cross-check bedside impression against a validated scoring rubric.
Use alongside PERC rule for low-risk PE rule-out workflows.
Compare original (weighted) scoring with simplified (1-point-per-criterion) model.

Frequently Asked Questions

Last updated: 2026-06-18 · Reviewed by Nham Vu