Fig. 3.
Decision-tree algorithm and scatter plot of baseline volumetric percentage of infection. Figure 2a demonstrates the decision-tree algorithm developed to classify COVID-19 pneumonia patients into common or severe group. Figure 2b compared baseline volumetric percentage between common and severe patients. The dotted line in black in Fig. 2b represents the cut-off value calculated by decision-tree. PPV positive predictive value; NPV negative predictive value
