Table 1.
Clinical and demographic composition of the cystic fibrosis data
| Characteristics | Development cohort (n = 24 704) | Validation cohort (n = 6175) |
|---|---|---|
| Birth cohort | ||
| <1981 | 5455 (22.1%) | 1336 (21.6%) |
| 1981 to 1988 | 4886 (19.8%) | 1220 (19.8%) |
| 1989 to 1994 | 4476 (18.1%) | 1090 (17.7%) |
| 1995 to 1998 | 2887 (11.7%) | 727 (11.8%) |
| 1999 to 2005 | 4642 (18.8%) | 1170 (18.9%) |
| >2005 | 2358 (9.5%) | 632 (10.2%) |
| Genotype (F508del mutation type) | ||
| Homozygous | 11 150 (45.1%) | 2851 (46.2%) |
| Heterozygous | 9884 (40%) | 2430 (39.4%) |
| Neither/unknown | 3670 (14.9%) | 894 (14.5%) |
| Male gender | 12 744 (51.6%) | 3211 (52%) |
| Age at baseline, mean; median (min‐max) | 16.6; 12.5 (6.0‐81.8) | 16.5; 12.4 (6.0‐79.0) |
| FEV1 at baseline mean; median (min‐max) | 79.8; 83.8 (9.3‐149.3) | 80.1; 82.9 (8.8‐143.4) |
| Medicaid insurance use | ||
| At baseline | 11 069 (44.8%) | 2759 (44.7%) |
| Ever during follow‐up | 19 032 (77%) | 4789 (77.6%) |
| Microbiology | ||
| Pseudomonas aeruginosa | ||
| At baseline | 6509 (26.3%) | 1646 (26.7%) |
| Ever during follow‐up | 18 434 (74.6%) | 4649 (75.3%) |
| Methicillin‐resistant Staphylococcus aureus | ||
| At baseline | 1774 (7.2%) | 472 (7.6%) |
| Ever during follow‐up | 10 821 (43.8%) | 2639 (42.7%) |
| CF‐related diabetes mellitus | ||
| At baseline | 1961 (7.9%) | 490 (7.9%) |
| Ever during follow‐up | 7525 (30.5%) | 1853 (30%) |
| Alive through follow‐up | 23 692 (95.9%) | 5927 (96%) |
Abbreviations: CF, cystic fibrosis; FEV1, forced expiratory volume in 1 second of percentage of predicted.