Research Article

The Clinical Significance of Procalcitonin Elevation in Patients over 75 Years Old Admitted for COVID-19 Pneumonia

Figure 1

Survival functions, determined by Cox regression analysis, of participants stratified according to levels of procalcitonin on admission (level 1: <0.05 ng/ml; level 2: ≥0.05 and <0.5 ng/ml; level 3: ≥0.5 and <2 ng/ml; level 4: ≥2 ng/ml) and age ((a) ; (b) ).
(a)
(b)