Figure 1.

Effects of long-term oxygen therapy on patients with COPD and hypoxemia,

from the Medical Research Council (MRC) trial and the Nocturnal Oxygen Therapy Trial (NOTT).

The figure shows survival data of men <70 years of age.

COT, continuous oxygen therapy (24-h O₂ supplementation per day);

NOT, nocturnal oxygen therapy (O₂ supplementation only at night);

MRC O₂, 15-h O₂ supplementation per day), MRC controls, no O₂ supplementation

(Figure taken from Stoller et al. 2010 [11]; reprinted with permission from Elsevier)