| Definition | Indicator may be reported using a number of definitions:
Iodine deficient school (narrow definition) = median urinary iodine concentration < 100mcg/litre
or
Iodine deficient school (comprehensive definition) = median urinary iodine concentration < 100mcg/litre or >= 20% of children with urinary iodine < 50mcg/litre
Iodine deficient child = urinary iodine concentration < 100mcg/litre
Indicator reported as proportion of schools or proportion of children as appropriate.
Note: The WHO definition of adequate iodine intake is a median urinary iodine concentration of >= 100mcg/litre and a goitre prevalence of less than 5%.
Since goitre prevalence was not related to urinary iodine levels in any school surveyed, this South African survey used an adapted definition. |