Number of subjects who underwent each test
| Females | Males | Total | |
| Spirometry | 231 (100) | 133 (100) | 364 (100) |
| Baseline P0.1/ respiratory pattern | 229 (99.1) | 132 (99.25) | 361 (99.2) |
| Hypercapnic response | 159 (68.8) | 86 (64.7) | 245 (67.3) |
| Polysomnographic study | 194 (84) | 104 (78.2) | 298 (81.87) |
| AHI | 192 (83.1) | 103 (77.4) | 295 (81.0) |
| Minimal Sp,O2 % | 195 (84.4) | 106 (79.7) | 301 (82.69) |
| Mean Sp,O2 % | 174 (75.3) | 96 (72.2) | 270 (74.2) |
| Body composition | 220 (95.2) | 125 (94.0) | 345 (94.8) |
| Leptin | 224 (97) | 131 (98.5) | 355 (97.5) |
| Waist | 223 (96.5) | 131 (98.5) | 354 (97.3) |
Data are presented as n (%). P0.1: mouth occlusion pressure; AHI: apnoea/hypopnoea index; Sp,O2: arterial oxygen saturation.