“…Obradovic et al, demonstrated significant antioxidant protection from NAC-P when compared with NAC. 12 In our study, potential confounding factors were limited as the two groups of patients (NAC and NAC-P) were not significantly different for variables: age, smoking status, cough status, expectoration, sputum appearance, sputum volume, microbiological sputum test, and CRP values. However, our study possessed several limitations.…”