Summary of CF and CF-RD diagnoses and carriers in study subgroups
| Presentation | Patients screened | Patients with variants detected (CF-causing, VCC and VUS) | Patients with CF-causing variants detected only | Total CF/CF-RD diagnoses (diagnostic frequency) | Total CF carriers† (carrier frequency) |
| Asymptomatic | |||||
| Carrier screening | 316 | 25 (7.91%) | 18 (5.70%) | N/A | 18 (5.70%) (0.15) |
| Symptomatic | |||||
| Clinical suspicion: respiratory | 453 | 24 (5.30%) | 22 (4.86%) | 9 (1.99%) (<0.0001****) | 15 (3.31%) (0.55) |
| Clinical suspicion: gastrointestinal | 45 | 7 (15.6%) | 7 (15.6%) | 2 (4.44%) (0.0002***) | 5 (11.1%) (0.033*) |
| Clinical suspicion: other | 31 | 2 (6.45%) | 2 (6.45%) | 1 (3.23%) (0.0123*) | 1 (3.23%) (>0.99) |
| Male infertility | 461 | 28 (6.07%) | 28 (6.07%) | 13 (2.82%) (<0.0001****) | 16 (3.47%) (0.48) |
| Foetal echogenic bowel | 603 | 29 (4.81%) | 24 (3.98%) | N/A‡ | 24 (3.98%) (>0.99) |
| Total | 1909 | 115 (6.02%) | 101 (5.3%) | 25 (2.5%) | 79 (4.1%) |
Values in non-bold brackets show diagnostic and carrier frequency calculated as a percentage of patients screened for that cohort. Values in bold brackets show statistical significance of diagnostic and carrier frequency compared with a population diagnostic frequency of 0.04% and population carrier frequency of 0.4%. Statistical significance was calculated using the Binomial test (*p<0.05, **p<0.01, ***p<0.001, ****p<0.0001). Exact p values are shown in brackets in bold.
†Total CF carriers calculated with patients carrying CF-causing variants only.
‡Three couples were both found to be carriers; prenatal testing found all three foetuses diagnosed with CF.
CF, cystic fibrosis; CF-RD, cystic fibrosis-related disorder; VCC, varying clinical consequences; VUS, variant of uncertain significance.