Adjust-Unlikely PE

A Pilot Study to Assess Feasibility of Evaluating the Safety and Efficiency of a Simplified Diagnostic Approach for Pulmonary Embolism

The aim of this pilot study is to assess the feasibility of a larger study to determine the Adjust-Unlikely algorithm safety and efficiency for diagnosing PE.

The pilot study objectives are to:

1. Determine study recruitment rate, per site, per month
2. Determine study 90-day loss to follow up rate
3. Estimate of the proportion of enrolled patients who test negative for PE at initial assessment using the Adjust-Unlikely rule
4. Estimate of the Adjust-Unlikely algorithm efficiency
5. Compare excluded and missed-eligible patients to study participants: age, sex and prevalence of PE diagnoses at initial testing.

The pilot study hypothesis is that the investigators can recruit at least 20 patients per month and successfully follow at least 90% of patients for 90 days.

Inclusion Criteria:

• Emergency physician decides to test for PE

Exclusion Criteria:

• Tested for PE without using the Adjust-Unlikely algorithm
• D-dimer level is known before Adjust-Unlikely assessment
• A new indication for anticoagulation on emergency department assessment (other than pulmonary embolism) in a patient not previously prescribed an anticoagulant
• Declines participation
• Is inaccessible for follow-up
• Has previously participated in this study