For the management of patients referred to respiratory triage during the early stages of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic, either chest radiography or computed tomography (CT) were used as first-line diagnostic tools. The aim of this study was to compare the impact on the triage, diagnosis and prognosis of patients with suspected COVID-19 when clinical decisions are derived from reconstructed chest radiography or from CT.

We reconstructed chest radiographs from high-resolution CT (HRCT) scans. Five clinical observers independently reviewed clinical charts of 300 subjects with suspected COVID-19 pneumonia, integrated with either a reconstructed chest radiography or HRCT report in two consecutive blinded and randomised sessions: clinical decisions were recorded for each session. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and prognostic value were compared between reconstructed chest radiography and HRCT. The best radiological integration was also examined to develop an optimised respiratory triage algorithm.

Interobserver agreement was fair (Kendall's W=0.365, p<0.001) by the reconstructed chest radiography-based protocol and good (Kendall's W=0.654, p<0.001) by the CT-based protocol. NPV assisted by reconstructed chest radiography (31.4%) was lower than that of HRCT (77.9%). In case of indeterminate or typical radiological appearance for COVID-19 pneumonia, extent of disease on reconstructed chest radiography or HRCT were the only two imaging variables that were similarly linked to mortality by adjusted multivariable models

The present findings suggest that clinical triage is safely assisted by chest radiography. An integrated algorithm using first-line chest radiography and contingent use of HRCT can help optimise management and prognostication of COVID-19.

对于在严重急性呼吸系统综合症冠状病毒 2 (SARS-CoV-2) 大流行的早期阶段转诊到呼吸道分诊的患者的管理，胸片或计算机断层扫描 (CT) 被用作一线诊断工具。本研究的目的是比较当临床决策来自重建胸片或 CT 时，对疑似 COVID-19 患者的分类、诊断和预后的影响。

我们从高分辨率 CT (HRCT) 扫描重建胸片。五名临床观察员独立审查了 300 名疑似 COVID-19 肺炎受试者的临床病历，并在连续两次盲法和随机会议中结合了重建的胸片或 HRCT 报告：记录了每次会议的临床决定。比较重建胸片与HRCT的敏感性、特异性、阳性预测值（PPV）、阴性预测值（NPV）和预后值。还检查了最佳放射学整合以开发优化的呼吸分类算法。

观察者间的一致性是公平的（Kendall's W =0.365，p<0.001）通过基于重建胸片的协议和良好的（Kendall's W =0.654，p<0.001）通过基于 CT 的协议。重建胸片辅助的 NPV（31.4%）低于 HRCT（77.9%）。对于 COVID-19 肺炎的不确定或典型的放射学表现，经调整的多变量模型，重建胸片或 HRCT 上的疾病程度是仅有的两个与死亡率类似的成像变量

目前的研究结果表明，胸片可以安全地辅助临床分诊。使用一线胸片和 HRCT 的综合算法可以帮助优化 COVID-19 的管理和预测。