Wells' Criteria for Pulmonary Embolism Calculator
The Wells' Criteria for Pulmonary Embolism stratifies pre-test probability of PE in adults with suspected acute PE. The original score totals 0–12.5 across seven items: clinical signs of DVT, PE as the most likely diagnosis, heart rate over 100, immobilisation or recent surgery, prior PE/DVT, haemoptysis, and active malignancy. The two-tier interpretation (≤ 4 vs > 4) drives whether D-dimer or imaging is the next reasonable step in many algorithms; the three-tier interpretation segments low, moderate, and high probability. The ACCP and ESC PE guidelines reference Wells' Criteria as a validated pre-test probability tool when paired with age-adjusted D-dimer.
This tool is for educational and decision-support use only. It does not replace independent clinical judgement. Always verify against the current guideline, FDA label, or specialty reference cited below before acting. Do not enter patient identifiers (name, MRN, dates of service).
Tool
Who this is for
- Emergency physicians evaluating chest pain and dyspnoea
- Internal medicine residents on inpatient PE workups
- APPs in urgent care and acute care settings
How to interpret the result
| Score / band | Interpretation |
|---|---|
| Two-tier ≤ 4 | PE unlikely — D-dimer is commonly the next step (age-adjusted thresholds where applicable). |
| Two-tier > 4 | PE likely — CT pulmonary angiography or V/Q is commonly the next step. |
| Three-tier < 2 | Low probability. |
| Three-tier 2–6 | Moderate probability. |
| Three-tier > 6 | High probability — proceed to imaging. |