Mean iodine concentration of household salt samples in the study population, n=48
| Study group | Mean (mg/kg) | SD | Range (min, max) | 95 % CI for mean | Comparison (P value) | |
| Lower | Upper | |||||
| Cases (n=24) | 10.3 | 16.2 | 0.01, 53.0 | 3.4 | 17.1 | 0.001* |
| Controls (n=24) | 21.1 | 17.0 | 1.1, 58.0 | 13.9 | 28.3 | |
| Total (n=48) | 15.7 | 17.3 | 0.01, 58.0 | 10.7 | 20.7 | |
Cases= patients with goitre; controls= patients without goitre.
*Mann-Whitney U-test, significant if p<0.05.