The Wells DVT Clinical Decision Rule (CDR) assigns a score from -2 to +9 based on clinical variables (e.g., active cancer, limb swelling, localized tenderness, prior history of DVT, alternative diagnosis as likely or more likely than DVT). In this study, the 3-level Wells DVT CDR was applied prospectively at presentation (Day 0) to participants with suspected recurrent DVT, using data collected from patient history and physical examination. Scores classify patients into low (≤0), moderate (1-2), or high (≥3) probability of DVT. Higher scores indicate greater probability of recurrent DVT. The outcome measure was the rate of confirmed recurrent DVT events within each Wells category, confirmed by objective imaging and adjudicated by an independent committee.

Of the 723 participants included in the study, 401 presented with suspicion of isolated DVT, without signs or symptoms of PE. Of the 401 presenting with suspicion of isolated DVT, 108 had a confirmed diagnosis of DVT.

The 3-level Wells PE score (range 0-12.5) was calculated from history and exam at the index visit. Scores ≤4 = PE unlikely, >4 = PE likely. Higher scores indicate greater likelihood of PE. The outcome is the proportion with confirmed recurrent PE at the index diagnostic work-up, adjudicated by blinded review of imaging.

Of the 723 participants enrolled, 268 presented with a suspicion of recurrent PE without concomitant DVT suspicion. Of the 268 presenting with suspicion of isolated PE, 79 had a confirmed diagnosis of PE.

The revised Geneva score (range 0-22) was calculated from history and exam at the index visit. Scores 0-3 = low, 4-10 = intermediate, ≥11 = high probability. Higher scores indicate greater likelihood of PE. The outcome is the proportion with confirmed recurrent PE at the index diagnostic work-up, adjudicated by blinded review of imaging.

Of the 723 participants included in the study, 268 presented with suspicion of PE, without signs or symptoms of DVT. Of the 268 presenting with suspicion of isolated PE, 79 had a confirmed diagnosis of PE.

D-dimer testing at the index visit was performed using the institutional cut-off for positivity in place during the study period (2014-2019). Results were classified as positive or negative. The outcome is the proportion with confirmed recurrent VTE in each test category at the index diagnostic work-up, adjudicated by blinded review of imaging.

Of the 723 participants in the study cohort, the attending physician ordered D-dimer testing in 482 at presentation for suspected recurrent VTE. This outcome measure is based on the 169 participants from that group who had negative D-dimer results and were evaluated for recurrent VTE.

The Wells DVT, Wells PE, and Geneva PE scores were calculated at the index visit in participants on anticoagulation. Score ranges and cut-offs as per respective rules. The outcome is the proportion with confirmed recurrent VTE in each risk category at the index diagnostic work-up, adjudicated by blinded review of imaging.

Of the 723 participants included, 38 were receiving anticoagulant therapy at the time of study inclusion and had a confirmed recurrent VTE. Of the 38 confirmed recurrent VTE events, 27 were for recurrent DVT and 11 were recurrent PE.

Number of participants who died from any cause from enrollment (Day 0) through Day 90 follow-up for those without confirmed recurrent VTE at enrollment.