| Variables | Initial cohort | Construction cohort | Validation cohort |
| Subjects n | 819 | 397 | 422 |
| Age years | 58.7±17.6 | 59.2±17.4 | 58.3±17.7 |
| Male | 356 (43.5) | 176 (44.3) | 180 (42.6) |
| Body mass index kg·m−2 | 25.7±4.7 | 26.1±4.28 | 25.35±4.98 |
| Dyspnoea mMRC score | 1.53±1.16 | 1.57±1.17 | 1.5±1.15 |
| Smoking pack-years | 5.79±18.1 | 5.59±18.23 | 5.96±17.9 |
| Appearance of sputum | |||
| Mucous | 199 (24.5) | 101 (25.4) | 98 (23.3) |
| Mucopurulent | 145 (17.7) | 106 (26.7) | 39 (9.3) |
| Purulent | 145 (17.7) | 40 (10.1) | 105 (25) |
| Respiratory insufficiency | 83 (10.1) | 39 (10.1) | 44 (10.6) |
| Number of affected lobes | 2.52±1.2 | 2.45±1.12 | 2.59±1.17 |
| Idiopathic bronchiectasis | 310 (37.9) | 154 (38.8) | 156 (37) |
| FEV1 % predicted | 68.9±25.9 | 68.5±25.6 | 68.7 (26.3) |
| FVC % predicted | 76.4±20.3 | 76±20.1 | 76.7±20.6 |
| Chronic colonisation | |||
| Pseudomonas aeruginosa | 260 (31.8) | 126 (31.8) | 134 (31.8) |
| Haemophilus influenzae | 126 (15.4) | 62 (15.6) | 64 (15.2) |
| Multiresistant Gram-negative bacteria | 40 (4.8) | 18 (4.5) | 22 (5.2) |
| Isolation of Staphylococcus aureus | 42 (5.1) | 19 (4.8) | 23 (5.5) |
| Isolation of fungi | 178 (21.7) | 87 (21.9) | 91 (21.9) |
| Isolation of atypical mycobacteria | 23 (2.8) | 14 (3.5) | 9 (2.1) |
| Exacerbations in previous year | 2.52±2.2 | 2.47±2.1 | 2.57±2.3 |
| Hospitalisations in previous year | 0.7±1.2 | 0.72±1.3 | 0.67±1.2 |
| Chronic treatment | |||
| Systemic antibiotics | 59 (7.2) | 28 (7.1) | 31 (7.35) |
| Inhaled antibiotics | 146 (17.8) | 75 (18.9) | 71 (16.8) |
| Macrolides | 110 (13.4) | 54 (13.6) | 56 (13.3) |
| Oral corticosteroids | 39 (4.7) | 18 (4.5) | 21 (4.9) |
| Death | 154 (18.8) | 79 (19.9) | 75 (17.8) |
Data are presented as mean±sd or n (%), unless otherwise stated. mMRC: modified Medical Research Council; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity.