Demographic data for treatment groups
| Air n=75 (52%) | Oxygen n=68 (48%) | p Value | |
| Age (years) | 72 (10.4) | 72 (9.2) | 0.90 |
| FEV1 (litres) | 1.17 (0.5) | 1.15 (0.5) | 0.84 |
| FEV1 % predicted | 47 (19.5) | 47 (18.3) | 0.98 |
| FVC (litres) | 2.59 (0.8) | 2.60 (0.9) | 0.93 |
| FVC % predicted | 79 (18.7) | 80 (22.9) | 0.79 |
| FEV1/FVC% | 42 (13.7) | 40 (12.5) | 0.40 |
| TLCO (ml/min/mm Hg) | 11.0 (4.0) | 12.3 (4.3) | 0.07 |
| TLCO % predicted | 44 (13.6) | 49 (14.6) | 0.02 |
| IC (litres) | 1.8 (0.6) | 1.9 (0.6) | 0.68 |
| IC % predicted | 83 (23.2) | 86 (20.4) | 0.35 |
| BMI (kg/m2) | 26.3 (6.5) | 27.7 (5.8) | 0.15 |
| Pao2 | 70.0 (8.4) | 72.6 (8.9) | 0.08 |
| Paco2 | 40.3 (4.7) | 40.7 (5.3) | 0.63 |
| BDI focal score | 3.4 (1.7) | 3.5 (2.0) | 0.80 |
| Exertional desaturation | 29 (39%) | 21 (31%) | 0.26 |
BDI, Baseline Dyspnoea Index; BMI, body mass index; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; IC, inspiratory capacity; TLCO, diffusing capacity of the lungs for carbon monoxide.