According to the SHAP test, the variables that could most effectively predict the development of severe respiratory failure were a low lymphocyte count, high left upper and right upper lung zone CT scores, a high neutrophil count, a small decrease in serum CRP levels on the third day of hospitalization, a high Charlson comorbidity index value, and high procalcitonin levels (Figure 5 and Figure 6). Here, CRP is linked to respiratory failure.