Figure 2From: Vitamin D supplementation during rehabilitation in COPD: a secondary analysis of a randomized trialChange in 25-OHD (Serum Vitamin D Level) in the vitamin D group (■) and in the placebo group (□). Data are expressed as mean ± SD. Baseline results are compared with results after 3 months of rehabilitation. Results with p <0.05 are indicated with (*).Back to article page