Brief Article
Copyright ©2013 Baishideng Publishing Group Co.
World J Respirol. Jul 28, 2013; 3(2): 29-37
Published online Jul 28, 2013. doi: 10.5320/wjr.v3.i2.29
Figure 1
Figure 1 Study flow chart. COPD: Chronic obstructive pulmonary disease.