Question

As per the World Health Organisation guidelines, iodine deficiency disorders are considered a public health problem in a community if the prevalence of goiter in school age children is more than:

• A. 1%
• B. 5%
• C. 10%
• D. 15%

Hint:

WHO uses total goiter rate in school children to grade IDD as a public health problem.

Answer 1

The Correct Option is B

Step 1: Recall how iodine deficiency is graded.
Iodine deficiency disorders (IDD) are graded using the total goiter rate (TGR) found on palpation of the thyroid in school age children, usually 6 to 12 years old, because this group reflects current iodine status well.

Step 2: Learn the WHO cut off for a public health problem.
The World Health Organisation, along with UNICEF and ICCIDD, states that a total goiter rate of 5% or more in school age children marks iodine deficiency as a problem of public health importance in that community.
Below 5%, the area is not classed as iodine deficient.

Step 3: Note the further severity bands.
Once the 5% mark is crossed, severity is graded further: 5.0 to 19.9% is mild, 20.0 to 29.9% is moderate, and 30% or more is severe iodine deficiency.

Step 4: Rule out the other options.
A prevalence of 1% is too low and falls within the normal range seen even in iodine sufficient areas.
Values of 10% and 15%, while they would already indicate iodine deficiency once the 5% threshold is crossed, are not themselves the WHO cut off point used to first label a community as iodine deficient.

Step 5: Final conclusion.
So the correct cut off used by WHO to call iodine deficiency disorder a public health problem is a goiter prevalence above 5% in school age children. This is option (B).