Clinical and demographic characteristics of the study population (study population and population included in the multivariable model)
| Baseline analysis | Multivariable model | |
| Male | 23 096/43 786 (52.75) | 8120/15 582 (52.11) |
| Socioeconomic status of country | ||
| High-income group | 29 918/43 786 (68.33) | 9781/15 582 (62.77) |
| Middle-income group | 10 042/43 786 (22.93) | 4336/15 582 (27.83) |
| Low-income group | 3826/43 786 (8.74) | 1465/15 582 (9.40) |
| Age at diagnosis, months | 42 023 | 15 582 |
| 4.86±10.49 | 3.0±7.06 | |
| 0.0–86.0 | 0.0–49.0 | |
| Age at diagnosis | ||
| 0 years | 23 744/42 023 (56.50) | 9731/15 582 (62.45) |
| 1–10 years | 12 160/42 023 (28.94) | 4400/15 582 (28.24) |
| 11–18 years | 2413/42 023 (5.74) | 732/15 582 (4.70) |
| >18 years | 3706/42 023 (8.82) | 719/15 582 (4.61) |
| BMI (first year in the ECFSPR) | 38 533 | NA |
| −0.43±1.18 | NA | |
| −1.07–0.36 | NA | |
| Neonatal screening | ||
| Not performed | 28 476/35 460 (80.30) | 11 074/15 582 (71.07) |
| Performed, result positive | 4668/35 460 (13.16) | 2987/15 582 (19.17) |
| Performed, result negative | 242/35 460 (0.68) | 175/15 582 (1.12) |
| Performed, result unknown | 2074/35 460 (5.85) | 1346/15 582 (8.64) |
| Meconium ileus at birth | ||
| No | 35 548/40816 (87.09) | 13 926/15 582 (89.37) |
| Yes, operated | 2791/40 816 (6.84) | 893/15 582 (5.73) |
| Yes, not operated | 869/40 816 (2.13) | 306/15 582 (1.96) |
| Yes, don't know if operated | 1608/40 816 (3.94) | 457/15 582 (2.93) |
| Chloride value, mmol·L−1 (sweat test) | 22 747 | 15 582 |
| 93.95±25.53 | 95.9±24.58 | |
| 97.00 (80.0–110.0) | 99.0 (83.0–110.0) | |
| 1.0–170.0 | 1.0–170.0 | |
| Mutation | ||
| Both class I/II | 9053/43 786 (20.68) | 3830/15 582 (24.58) |
| Both F508del | 17 133/43 786 (39.13) | 6311/15 582 (40.50) |
| At least one of class III | 1393/43 786 (3.18) | 562/15 582 (3.61) |
| At least one of class IV | 3006/43 786 (6.87) | 1152/15 582 (7.39) |
| At least one of class V | 2501/43 786 (5.71) | 987/15 582 (6.33) |
| One of class I/II, other mutation in class unknown or both mutations unknown or genetic test not performed | 10 520/43 786 (24.03) | 2740/15 582 (17.58) |
Data are presented as number of subjects with specific characteristics/total number of subjects with information on the variable (%), n, mean±sd, range or median (interquartile range). BMI: body mass index; ECFSPR: European Cystic Fibrosis Society patient registry; NA: not applicable.