RESUMEN
By applying the WHO/UNICEF/ICCIDD guidelines for the Assessment of Iodine Deficiency Monitoring using Thyroid Stimulating Hormone (TSH) with the use of a Geographic Information System technique, the degree of severity of iodine deficiency for various areas can be evaluated. In this study, TSH data for neonates born in all 76 provinces of Thailand during 2003-2006 were classified according to their spatial demographic information. The results show that all provinces in Thailand suffer from iodine deficiency at mild to moderate levels, and the degree of severity increases year by year. The number of provinces with iodine deficiency were 10, 12, 35 and 36 for the years 2003, 2004, 2005 and 2006, respectively. This trend shows that each province in Thailand is at risk for iodine deficiency. Public health decision makers need to be aware of this problem anddevelop a program to eliminate iodine deficiency.