highly significantp-value < 0.001
Among the smokers, the value was even higher in COPD patients (mean value of 10.45 ± 3.03 ppm) in contrast to others (7.05 ± 1.56 ppm) but was highly significant (p-value < 0.001).
Among the smokers, the value was even higher in COPD patients (mean value of 10.45 ± 3.03 ppm) in contrast to others (7.05 ± 1.56 ppm) but was highly significant (p-value < 0.001).