# Wells Score for Pulmonary Embolism (PE)

Calculate the Wells score to estimate clinical probability of pulmonary embolism (PE). Components: clinical signs/symptoms of DVT (+3), PE is the most likely diagnosis (+3), heart rate >100 (+1.5), immobilization ≥3 days or surgery in last 4 weeks (+1.5), previous objectively diagnosed DVT/PE (+1.5), hemoptysis (+1), active malignancy (+1). Reports BOTH endorsed interpretations: three-tier (low <2 ~1.3%, moderate 2–6 ~16.2%, high >6 ~37.5%) and dichotomized two-tier (PE unlikely ≤4 ~12.1% — a negative D-dimer can rule out; PE likely >4 ~37.5% — imaging required). Derived from Wells 2001 (Ann Intern Med), ACEP 2018 clinical policy, and the ESC 2019 PE guideline. Pair with PERC and D-dimer. Not medical advice.

> Canonical page: https://elysiatools.com/en/tools/wells-pe-score

- **Category:** Health

- **Keywords:** Wells, pulmonary embolism, PE, venous thromboembolism, VTE, D-dimer, CTPA, clinical prediction rule, PERC, emergency

## Overview

The Wells Score for Pulmonary Embolism calculator estimates the clinical probability of PE from seven yes-or-no criteria, including DVT signs, tachycardia, recent immobilization or surgery, previous DVT or PE, hemoptysis, and active malignancy. It reports both three-tier and two-tier interpretations. This tool is not medical advice.

## Inputs

- **Clinical signs and symptoms of DVT** (checkbox): Leg swelling and pain with palpation of the deep veins. +3.
- **PE is the most likely diagnosis** (checkbox): PE is the #1 or equally likely diagnosis (alternative diagnosis less likely than PE). +3.
- **Heart rate > 100 beats/min** (checkbox): Heart rate > 100 beats/min. +1.5.
- **Immobilization ≥ 3 days or surgery in last 4 weeks** (checkbox): Recent immobilization ≥3 days or surgery within the last 4 weeks. +1.5.
- **Previous objectively diagnosed DVT/PE** (checkbox): Previous objectively diagnosed DVT or PE. +1.5.
- **Hemoptysis** (checkbox): Hemoptysis. +1.
- **Active malignancy** (checkbox): Active malignancy (treatment ongoing, palliative, or within last 6 months). +1.

## When to use

- Estimate the pretest clinical probability of pulmonary embolism using the Wells criteria.
- Review how selected PE risk factors contribute to the total score.
- Compare the three-tier interpretation with the two-tier PE-unlikely or PE-likely interpretation.

## How it works

- Select the checkbox for each Wells criterion that applies to the patient.
- The calculator adds the assigned points: 3, 1.5, or 1 point depending on the criterion.
- The result reports the total Wells PE score and its three-tier category.
- It also reports the two-tier interpretation: PE unlikely at 4 points or less, or PE likely above 4 points.

## Use cases

- Emergency assessment of suspected pulmonary embolism.
- Teaching the point values and interpretation of the Wells clinical prediction rule.
- Documenting a structured pretest probability assessment before further PE evaluation.

## Frequently asked questions

### What does the Wells PE calculator measure?

It estimates the clinical probability of pulmonary embolism using seven established criteria.

### Which criteria are included?

The criteria include DVT signs, PE as the most likely diagnosis, heart rate above 100, recent immobilization or surgery, previous DVT or PE, hemoptysis, and active malignancy.

### How are the results interpreted?

Three-tier results are low below 2, moderate from 2 to 6, and high above 6. Two-tier results classify PE as unlikely at 4 or less and likely above 4.

### Can this score diagnose pulmonary embolism?

No. It estimates clinical probability and must be interpreted with the patient's assessment and appropriate testing.

### What should be used with the Wells score?

The tool metadata recommends pairing the score with PERC and D-dimer assessment when clinically appropriate.

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