The age and sex distribution of the hypotonic group and the isotonic group
| Hypotonic | Isotonic | P value | |
| n | 646 | 807 | |
| Number of tests (median (IQR)) | 2 (1, 5) | 2 (1, 4) | 0.07 |
| Age (%) | 0.2 | ||
| 0–1 months | 106 (16) | 168 (21) | |
| 1–6 months | 140 (22) | 175 (22) | |
| 6–24 months | 119 (18) | 129 (16) | |
| Above 24 months | 281 (44) | 335 (42) | |
| Sex=male (%) | 374 (58) | 493 (61) | 0.2 |