The nomogram (Fig. 5) was developed by the CR model in the primary cohort, with the factors of the total number of mixed GGO in peripheral area (TN_Mixed_GGO_IP), tree-in-bud, offending vessel augmentation in lesions (OVAIL), respiration, heart ratio, temperature, white blood cell count, cough, fatigue and lymphocyte count category incorporated. The total points were calculated by summing the points identified on the “points” scale for each factor. By comparing the “total points” scale and the “probability” scale, the individual probability of COVID-19 infection could be obtained.
Fig. 5 Nomogram of the CR model in the primary cohort. TN_Mixed_GGO_IP represented the total number of mixed GGO in peripheral area. AVAIL represented offending vessel segmentation in lesions. N was a negative result, and P was a positive result. Norm represented normal. Note that in probability scale, 0 = non-COVID-19, 1 = COVID-19