The prevalence of iodine deficiency disorder in two different populations in northern province of Iran: a comparison using different indicators recommended by WHO. 
Comparison of the prevalence of iodine deficiency disorder (IDD) in neonates and school children using two different WHO indicators.  From 2006 to 2010, 119701 newborns were screened by measurement of serum TSH level by heel prick.  Neonates who had blood TSH ≥ 5 mIU/l were recalled for more evaluation.  In the same period of time, urine iodine was measured in 1200 school-aged children.  The severity of IDD was classified using WHO, UNICEF, ICCIDD criteria.  Between 2006 and 2010 a total of 138832 neonates were screened in Guilan province and the total recall rate (neonates with TSH level ≥ 5 mIU/l) was 1.8 %.  The incidence rate of Congenital Hypothyroidism (CH) was 1/625.  The median urine iodine level in school-aged children was 200-299 μg/l. Considering the WHO, UNICEF, ICCIDD criteria, Guilan province would be classified as a none-IDD endemic area.  However, health care systems should pay attention to the iodine excess and the risk of iodine induced hyperthyroidism in this population.