Results of the NETT trial
| Outcome | Baseline | 6 months | 12 months | 24 months |
| >10 W increase in exercise capacity % | NA | 28 versus 4 | 22 versus 5 | 15 versus 3 |
| Mean Pa,O2 mmHg | 65 versus 65 | 70 versus 64 | 69 versus 64 | 68 versus 62 |
Pa,O2: arterial oxygen tension; NA: not applicable. Data taken from [27–29].