Composition of the three patient groups
| S | Non-S | Post-S | |
| Year of birth | 1973–1979 | 1973–1979 | 1979–1985 |
| Number of patients | 24 (19+5) | 29 | 39 |
| Frequency of cystic fibrosis at birth | 1:3918 | 1:4033 | 1:5640 |
| Number of patients in clinical database | 24 | 29 | 34 |
| Age at diagnosis months | |||
| Total | 1.0 (0.1–120.0) | 18.0 (0.3–220.0) | 22.5 (0.1–89.0) |
| Excluding patients ileus | 1.7 (0.2–120.0) | 21.0 (0.3–220.0) | 27.0 (0.1–89.0) |
| Excluding patients with false-negative screening tests | 0.8 (0.1–43.0) | ||
| Meconium ileus | 4 (16.7%) | 2 (6.9%) | 11 (32.3%) |
| Death before the start of study | 4 (16.7%) | 5 (17.2%) | 1 (2.9%) |
| Lost to follow-up | 2 | 0 | 1 |
| Exclusion from stiidy | 0 | 0 | 3 |
Age data are presented as median (range)
S: patients detected by screening
Non-S: patients detected by clinical symptoms
Post-S: patients born after the end of the screening programme detected by clinical symptoms
patients born in the screened birth cohort with false negative screening tests
exclusion from study due to comorbidity