Simplification of the revised Geneva score for assessing clinical probability of pulmonary embolism.

BACKGROUND The revised Geneva score is a fully standardized clinical decision rule (CDR) in the diagnostic workup of patients with suspected pulmonary embolism (PE). The variables of the decision rule have different weights, which could lead to miscalculations in an acute setting. We have validated a simplified version of the revised Geneva score. METHODS Data from 1049 patients from 2 large prospective diagnostic trials that included patients with suspected PE were used and combined to validate the simplified revised Geneva score. We constructed the simplified CDR by attributing 1 point to each item of the original CDR and compared the diagnostic accuracy of the 2 versions by a receiver operating characteristic curve analysis. We also assessed the clinical utility of the simplified CDR by evaluating the safety of ruling out PE on the basis of the combination of either a low-intermediate clinical probability (using a 3-level scheme) or a "PE unlikely" assessment (using a dichotomized rule) with a normal result on a highly sensitive D-dimer test. RESULTS The complete study population had an overall prevalence of venous thromboembolism of 23%. The diagnostic accuracy between the 2 CDRs did not differ (area under the curve for the revised Geneva score was 0.75 [95% confidence interval, 0.71-0.78] vs 0.74 [0.70-0.77] for the simplified revised Geneva score). During 3 months of follow-up, no patient with a combination of either a low (0%; 95% confidence interval, 0.0%-1.7%) or intermediate (0%; 0.0%-2.8%) clinical probability, or a "PE unlikely" assessment (0%; 0.0%-1.2%) with the simplified score and a normal result of a D-dimer test was diagnosed as having venous thromboembolism. CONCLUSION This study suggests that simplification of the revised Geneva score does not lead to a decrease in diagnostic accuracy and clinical utility, which should be confirmed in a prospective study.