Variables involved in calculating the severity score in the Bronchiectasis severity index
| Factor and points for scoring system | ||||
| Age (years) | <50 (0 points) | 50–69 (2 points) | 70–79 (4 points) | >80 (6 points) |
| BMI (Kg/m2) | <18.5 (2 points) | 18.5–25 (0 points) | 26–30 (0 points) | >30 (0 points) |
| FEV1% predicted | >80 (0 points) | 50–80 (1 point) | 30–49 (2 points) | <30 (3 points) |
| Hospital admission within last 2 years | No (0 points) | Yes (5 points) | ||
| Number of exacerbations in previous 12 months | 0 (0 points) | 1–2 (0 points) | ≥3 (2 points) | |
| MRC breathlessness score | 1–3 (0 points) | 4 (2 points) | 5 (3 points) | |
| P. aeruginosa colonisation | No (0 points) | Yes (3 points) | ||
| Colonisation with other organisms | No (0 points) | Yes (1 point) | ||
| Radiological severity | <3 lobes affected (0 points) | ≥3 lobes or cystic bronchiectasis in any lobe (1 point) | ||
0-4 Points=mild disease; 5–8=moderate disease; 9 and over=severe disease.