Serum ECP levels (μg/l) in normal subjects and patients with nasal polyps
| Normal values (<20 μg/l) | High values (>20 μg/l) | Mean (SE) | p value | |
| Normal subjects (n = 99) | 99 | – | 5.5 (0.31) | |
| Patients with polyps (n = 53) | 23 – | – 30 | 11.27 (5.62) 67.5 (48.2) | <0.0001 |
| Patients with aspirin disease (n = 8) | 4 – | – 4 | 14.2 (6.5) 48.7 (12.4) | NS |