Comparison on predictive effect of two kinds of scales for pulmonary embolism among patients with abnormal D-dimer

Abstract

Objective To explore the predictive effect of original Wells Scale and revised Geneva Scale for pulmonary embolism (PE) by receiver operating characteristic (ROC) curve among patients with abnormal D-dimer (≥500 μg/L) so as to reduce the misdiagnosis of PE. Methods From January 2018 to March 2018, we selected 207 abnormal D-dimer patients with suspected PE (84 cases diagnosed as PE by CTPA and 123 cases excluded from PE) from 10 departments at a ClassⅢ Grade A hospital in Ningbo City as subjects by convenience sampling. Patients' data were collected with the general information scale, original Wells Scale and revised Geneva Scale, and the predictive value of two kinds of scale were analyzed and compared. Results The Cronbach's α reliability coefficient, half reliability and content validity of the original Wells Scale were higher than those of the revised Geneva Scale (0.877 vs. 0.679, 0.792 vs. 0.673, 0.577 vs. 0.547) . The area under ROC curve of the original Wells Scale was 0.902 [95%CI: (0.853, 0.939) ]with Wells Score >1.5 for the cut-off value, 96.43% for the sensitivity, 70.73% for the specificity, 3.29 for the positive likelihood and 0.05 for the negative likelihood. The area under ROC curve of the revised Geneva Scale was 0.894 [95%CI: (0.844, 0.932) ]with Wells Score >5 for the cut-off value, 85.71% for the sensitivity, 85.31% for the specificity, 5.86 for the positive likelihood and 0.17 for the negative likelihood. Conclusions Two kinds of scale are all value for predicting PE of abnormal D-dimer patients. However, the sensitivity and specificity of the original Wells Scale are higher than those of the revised Geneva Scale with low missed diagnosis rate which more suitable for predicting PE of abnormal D-dimer patients. Key words: Pulmonary embolism; D-dimer; Prediction; Original Wells Scale; Revised Geneva Scale