In the ROC analysis, the optimal positive cut-off values to determine the need for intensive care in COVID-19 patients were as follows: 10.5 for the lung CT involvement score (sensitivity: 0.842; specificity: 0.823; P ≤ .001); 64 years for age (sensitivity: 0.737; specificity: 0.823; P  = .001); 20.7 mg L-1 for CRP (sensitivity: 0.895; specificity: 0.661; P  = .001); 805 ng mL-1 for d-dimer (sensitivity: 0.632; specificity: 0.798; P  = .001); and 211 ng mL-1 for ferritin (sensitivity: 0.842; specificity: 0.645; P  = .001) (Figure 3). The gene discussed is CRP; the disease is COVID-19.