Specifically, the SFR (oxygen saturation/supplementary oxygen and the measure of severity of respiratory failure) was associated with the chest radiograph opacification score with an r value of −0.38 (95% confidence intervals CI: −0.45 to −31, p < 0.0001, Pearson's correlation coefficient), and the serum CRP (the measure of systemic inflammation) had a r value of +0.33 (95% CI: +0.24 to +0.41, p < 0.0001, Pearson's correlation coefficient). This evidence concerns the gene CRP and respiratory failure.