The most severe endemia of our time, iodine deficiency affects more than one billion people worldwide. Two hundred Million cases of goiter and six million of creatinism have recorded worldwide.

Iodine deficiency disorders (IDD) is the most health problem of our country.

In a prospective study, the prevalence and clinical staging of endemic goiter in 16054 students (8262 male and 7792 female) age range 7-18 years old in different cities of Hamadan were determined.

By clinical examination, the goitrous thyroid was classified based on the WHO staging system

The prevalence of goiter were 39.76% in males and 47.38% in females of total sample.

The most common stage, was IA (34.05%) and IB (8.54%) respectively. Only 9.97% of population had class II goiter. Class IA goiter were more common in male (34.83%) than female (32.26%) but class IB and II were more common in female students.

Conclusion:

The older the person, higher the prevalence of goiter in both males and females.

The prevalence rate of goiter is significantly more in females than males.

The prevalence of high stage (IB, II) were more in Hamadan and Touiserkan.

According to WHO recommendations goiter must be considered an important health problem in Hamadan Province.