Table 4.
Multiple linear regression with variables independently related to urinary iodine concentration (UIC)*, considering all collected samples (n 896), in women from the state of Rio de Janeiro, Brazil, September 2014–February 2017
| β | 95 % CI | t | P | |
|---|---|---|---|---|
| Age (years)* | −0·44 | −0·71, −0·17 | −3·17 | <0·01 |
| BMI (kg/m2)* | 0·25 | 0·00, 0·50 | 1·97 | 0·05 |
| Multiparity | 0·15 | 0·02, 0·28 | 2·23 | 0·03 |
Variables included in the model: age*, gestational week*, serum thyrotropin (mIU/l)* and free thyroxine (ng/dl)* (at the time of UIC collection), iodine concentration in salt (mg/kg)*, first-trimester BMI*, smoking habit, positive serum thyroid antibodies (thyroperoxidase antibody and/or thyroglobulin antibody) and multiparity (≥3 labours).
Only those correlations with P≤0·100 are shown in the table.
*
After logarithmic transformation.