[Assessing the effectiveness of removing iodized salt on iodine excessive goiter using thyroid volume reference for...

Using the thyroid volume criteria for body surface area (BSA) to assess more precisely the effectiveness of removing iodized salt on the goiter status of children living in areas with excessive iodine in drinking water.

Three towns with median water iodine (MWI) of 150-300 µg/L were selected by simple random method in Hengshui city of Hebei province of China in May of 2010. A total of 452 and 459 children in the 3 towns were randomly selected to measure thyroid volume by ultrasound. Iodized salt was removed in July of 2010. In October of 2013, 459 children in these 3 towns were selected by simple random method to measure their thyroid volume by ultrasound again. Their goiter status was judged using the criteria of thyroid volume for BSA recommended by the WHO.

After removing iodized salt, the overall BSA specific goiter prevalence in the three towns significantly decreased from 33% (149/452) to 6% (30/459) (χ² = 100.64, P < 0.001). The BSA specific goiter prevalence in 8, 9 and 10 year-old children decreased respectively from 38% (35/92), 31% (59/193) and 33% (55/167) to 6% (10/164), 7% (11/163) and 7% (9/132) (χ² values were 41.35, 31.66, 29.79, P < 0.001). The BSA specific goiter prevalence in boys and girls decreased from 34% (83/244) and 32% (66/208) to 6% (14/225) and 7% (16/234) (χ² values were 55.01, 45.06, P < 0.001) respectively.

The BSA specific children's goiter prevalence decreased significantly after removing iodized salt from their diet in the HIA in Hebei province.