Close | |
Figure 2 Levels of vitamin D in nmol/l plotted against (a) COPD GOLD groups (1=GOLD A, 2=GOLD B, 3=GOLD C, and 4=GOLD D), (b) against forced expiratory volume in first second (FEV1), (c) exacerbation rate, and (d) hospital days. P<0.05, significant. |
|