Wells' Criteria for Pulmonary Embolism
The Wells’ Criteria risk stratifies patients for pulmonary embolism (PE) and provides an estimated pre-test probability. The physician can then chose what further testing is required for diagnosing pulmonary embolism (I.E. d-dimer or CT angiogram).
The Wells’ Criteria risk stratifies patients for pulmonary embolism (PE), and has been validated in both inpatient and emergency department settings. Its score is often used in conjunctiion with d-dimer testing to evaluate for PE.
- There must first be a clinical suspicion for PE in the patient (this should not be applied to all patients with chest pain or shortness of breath, for example).
- Wells' can be used with either 3 tiers (low, moderate, high) or 2 tiers (unlikely, likely). We recommend the two tier model as this is supported by ACEP’s 2011 clinical policy on PE. (See Next Steps)
- Wells’ is often criticized for having a “subjective” criterion in it (“PE #1 diagnosis or equally likely”)
- Wells’ is not meant to diagnose PE but to guide workup by predicting pre-test probability of PE and appropriate testing to rule out the diagnosis.
- The Wells’ Score has been validated multiple times in multiple clinical settings.
- Physicians have a low threshold to test for pulmonary embolism.
- The score is simple to use and provides clear cutoffs for the predicted probability of pulmonary embolism.
- The score aids in potentially reducing the number of CTAs performed on low-risk PE patients.