General characteristics of the patients with CF and without CF included in the primary analysis
| Sweat chloride | P value* | ||
| Positive | Negative | ||
| N (%) | N (%) | ||
| Age-group | 0.30 | ||
| Newborns | 13 (19.1) | 161 (14.5) | |
| Infants | 55 (80.9) | 947 (85.5) | |
| Sex | 0.86 | ||
| Female | 35 (51.5) | 555 (50.1) | |
| Male | 33 (48.5) | 546 (49.3) | |
| Not recorded | 0 | 7 (0.6) | |
| Region of residence | 0.01 | ||
| Urban area | 8 (11.8) | 277 (25.0) | |
| Rural area | 60 (88.2) | 831 (75.0) | |
| Gestational age (weeks) | 0.03 | ||
| <37 | 1 (1.5) | 102 (9.2) | |
| >37 | 61 (89.7) | 999 (90.2) | |
| Not recorded | 6 (8.8) | 7 (0.6) | |
| Birth weight (g) | 0.21 | ||
| <2.500 | 5 (7.4) | 142 (12.8) | |
| >2.500 | 60 (88.2) | 954 (86.1) | |
| Not recorded | 3 (4.4) | 12 (1.1) | |
| Weight at the tests day (g) | 1.00 | ||
| <2.000 | zero | 4 (0.4) | |
| >2.000 | 36 (52.9) | 1061 (95.8) | |
| Not recorded | 32 (47.1) | 43 (3.8) | |
*χ2 or Fisher’s exact test.
CF, cystic fibrosis.