Summary

A clinical predictive model that accurately identifies patientswith pulmonary embolism who are at low risk of adverse medicaloutcomes may be useful for management decisions, such asoutpatient treatment. We aimed to externally validate a previouslyderived prognostic score identifying emergency wardpatients with acute pulmonary embolism at low risk of 3-month complications. One hundred and ninety-nine consecutivepatients with proven pulmonary embolism were includedfrom the emergency centres of three teaching and general hospitals.Adverse outcomes, such as death, major bleed, or recurrentvenous thromboembolism, were recorded during a 3-month follow-up. We retrospectively computed the prognosticscore for each patient and determined its predictive accuracyat different threshold values. The overall 3-month risk of adverse event after the diagnosis of pulmonary embolism was9.5%. At a threshold of 2 points, eight patients with scores ator below the cut-off (5%; 95% CI 2.6-9.6) and 11 patients withscores above this cut-off (27.5%; 95% CI 16.1-42.8) presented acomplication.The negative predictive value for an adverse outcomewas 95.0% (95% CI 90.4-97.4). The receiver operatingcharacteristic curve derived from the score distribution had anarea of 0.77 (95% CI 0.65-0.89).This compared favourably withthe characteristics of the derivation study. We conclude thatthe Geneva risk score has an acceptable predictive accuracy toidentify patients with pulmonary embolism at low risk for 3-month adverse outcomes.Whether this score remains accurateand useful in clinical practice should be determined in a prospectivemulticentre validation study.