title: Sex and age correlated reference values of serum thyroglobulin measured by a modified radioimmunoassay.
abstract: The aim of the present investigation was to describe variations in serum thyroglobulin in relation to sex and age in a group of normal persons. The method used was a modified double antibody radioimmunoassay characterized by pre-incubation at 37 degrees C of standard or sample with antiserum, resulting in a reduced total incubation time. Both sensitivity and precision were comparable to other published methods. Of the 152 blood-donors initially investigated, 7 were excluded due to the presence of antithyroglobulin antibodies as evidenced by a radioassay. Both sexes were equally represented with an even distribution of ages from 20-65 years. Increased serum thyroglobulin with increasing age was demonstrated, the correlation being significant in women (Kendall's tau, P less than 0.001). Detectable concentrations of serum thyroglobulin (above 1.7 microgram/1) were found in 94%. Based on the logarithmic transformation, the upper reference limits were determined for men less than or equal to 40 years: 36 microgram/l, greater than 40 years: 44 microgram/l (difference between groups not significant, P greater than 0.05), and for women less than or equal to 40 years: 30 microgram/l, greater than 40 years: 60 microgram/l (significant difference, P less than 0.005).
mesh_terms: D000328:Adult; D000367:Age Factors; D001323:Autoantibodies / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D012016:Reference Values; D012737:Sex Factors; D013954:Thyroglobulin / Q000097:blood* / Q000276:immunology; D013972:Thyrotropin / Q000097:blood
chemical_list: D001323:Autoantibodies; D013972:Thyrotropin; D013954:Thyroglobulin