Despite the high risk of bias of many of the included studies , the results suggested that urinary iodine , thyroglobin , serum thyroxine , and thyroid-stimulating hormone are useful biomarkers of iodine status , at least in some groups .
BACKGROUND Biomarkers of iodine status are required to study iodine deficiency disorders in different parts of the world and to evaluate the effects of fortification strategies .
OBJECTIVE The objective was to assess the usefulness of biomarkers of iodine status in humans by systematic ally review ing intervention studies that altered iodine status .
Development of a dried whole-blood spot thyroglobulin assay and its evaluation as an indicator of thyroid status in goitrous children receiving iodized salt.
BACKGROUND Serum thyroglobulin appears to be a sensitive marker of thyroid dysfunction in endemic goiter . However , its value as an indicator of thyroid status in children after the introduction of iodized salt  has not been tested . OBJECTIVE The objective was to optimize and vali date a thyroglobulin assay on dried whole blood spots and to evaluate thyroglobulin as an indicator of thyroid response to iodized salt . DESIGN A st and ardized , commercially available , s and wich fluoroimmunometric serum thyroglobulin assay was adapted for use on blood spots and vali date d in Swiss children . In a 1-y prospect i ve study in 377 goitrous Moroccan children aged 6 - 15 y , the assay was used to measure thyroglobulin before and after the introduction of iodized salt .  Urinary iodine , thyroid volume , thyrotropin , and thyroxine were measured , and regression was done with thyroglobulin as the dependent variable . RESULTS Correlation between the blood spot and serum assays was excellent ( r = 0.98 ) . The SD of the difference between the blood spot and serum assays was 3.8 micro g/L ; the median CVs for the blood spot assay in controls and sample s were 6.3 % and 14.4 % , respectively . Median thyroglobulin was 24.5 ( range : 0 - 328.8 ) micro g/L at baseline and fell significantly after the introduction of iodized salt to 6.2 ( 0 - 83.1 ) and 4.4 ( 0 - 47.1 ) micro g/L at 5 and 12 mo , respectively ( P < 0.0001 ) . Regression of urinary iodine and thyroid volume on thyroglobulin was highly significant at baseline and at 5 mo ( P < 0.001 ) . CONCLUSION Thyroglobulin , measured in dried whole blood spots , may be a valuable indicator of improving thyroid function in children after supplementation with iodized salt
Despite the high risk of bias of many of the included studies , the results suggested that urinary iodine , thyroglobin , serum thyroxine , and thyroid-stimulating hormone are useful biomarkers of iodine status , at least in some groups .
BACKGROUND Biomarkers of iodine status are required to study iodine deficiency disorders in different parts of the world and to evaluate the effects of fortification strategies .
OBJECTIVE The objective was to assess the usefulness of biomarkers of iodine status in humans by systematic ally review ing intervention studies that altered iodine status .