Wells Criteria Calculator — Assess DVT and Pulmonary Embolism Risk

Wells Criteria Calculator

Calculate Wells Criteria scores for Deep Vein Thrombosis (DVT) and Pulmonary Embolism (PE). Assess clinical probability and determine appropriate diagnostic approach.

Step 1: Select Wells Criteria Type

Clinical Symptoms of DVT

Active cancer (patient receiving treatment for cancer within the previous 6 months or currently receiving palliative treatment)
+1 point
Paralysis, paresis, or recent plaster immobilization of the lower extremities
+1 point
Recently bedridden for more than 3 days or major surgery within the previous 12 weeks requiring general or regional anesthesia
+1 point
Localized tenderness along the distribution of the deep venous system
+1 point
Entire leg swollen
+1 point
Calf swelling more than 3 cm compared with asymptomatic calf (measured 10 cm below tibial tuberosity)
+1 point
Pitting edema confined to the symptomatic leg
+1 point
Collateral superficial veins (nonvaricose)
+1 point
Previously documented DVT
+1 point
Alternative diagnosis at least as likely as DVT
-2 points

About Wells Criteria

The Wells Criteria are clinical prediction rules used to determine the pre-test probability of Deep Vein Thrombosis (DVT) or Pulmonary Embolism (PE). These scores help guide diagnostic testing and treatment decisions.

Step 2: Additional Information

Clinical Interpretation

DVT Wells Score:
≤0 points: Low probability (3% risk)
1-2 points: Moderate probability (17% risk)
≥3 points: High probability (75% risk)

PE Wells Score:
≤4 points: Low probability (1.3% risk)
4.5-6 points: Moderate probability (16.2% risk)
>6 points: High probability (37.5% risk)

Wells Criteria Results

Score Summary
Clinical Interpretation
Management Recommendations

Wells Criteria Score

2
Low Clinical Probability
DVT Probability
3%
PE Probability
1.3%
Recommended Test
D-dimer
Next Steps
Consider D-dimer testing

Clinical Probability Interpretation

Low Probability (Wells DVT ≤0, Wells PE ≤4)
Unlikely to have DVT/PE. Consider alternative diagnoses.
Recommended action: D-dimer testing. If negative, no further testing needed. If positive, proceed to ultrasound (DVT) or CTPA (PE).
Moderate Probability (Wells DVT 1-2, Wells PE 4.5-6)
Moderate suspicion for DVT/PE. Further testing recommended.
Recommended action: D-dimer testing followed by ultrasound (DVT) or CTPA (PE) if D-dimer positive.
High Probability (Wells DVT ≥3, Wells PE >6)
High suspicion for DVT/PE. Prompt diagnostic evaluation needed.
Recommended action: Immediate imaging with ultrasound (DVT) or CTPA (PE). Consider starting anticoagulation while awaiting results.

Important Notes

The Wells Criteria is a clinical prediction tool, not a definitive diagnostic test. Clinical judgment should always be used in conjunction with this calculator. All results should be interpreted by a qualified healthcare professional.

Management Recommendations Based on Wells Score

Wells Score Clinical Probability Recommended Diagnostic Approach Treatment Considerations
≤0 (DVT)
≤4 (PE)		 Low D-dimer testing. If negative, no further testing needed. No anticoagulation unless imaging confirms DVT/PE.
1-2 (DVT)
4.5-6 (PE)		 Moderate D-dimer testing. If positive, proceed to ultrasound (DVT) or CTPA (PE). Consider prophylactic anticoagulation while awaiting test results in high-risk patients.
≥3 (DVT)
>6 (PE)		 High Immediate imaging with ultrasound (DVT) or CTPA (PE). D-dimer is not helpful in high probability cases. Strongly consider starting therapeutic anticoagulation while awaiting diagnostic confirmation.

Clinical Pearls

• Wells Criteria should be applied before any diagnostic testing for DVT/PE.
• The two-level Wells score for PE (PE likely/unlikely) is commonly used in practice.
• Always consider patient-specific factors and comorbidities when interpreting results.
• In pregnant patients, Wells Criteria can be used but ultrasound is preferred over D-dimer due to physiological elevation of D-dimer in pregnancy.

Related Medical Calculators

Important Medical Disclaimer

This Wells Criteria Calculator is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

Consult a Healthcare Professional