Diagnostic Studies of Thyroid Function Statistical Evaluation of Results from the Standard Radioiodine Test and a Procedure for Fractionation of Plasma Radioactivity

Abstract

A 4-year material of radioiodine tests, including separation of plasma radioactivity into 4 fractions, has been subjected to an extensive statistical analysis in order to evaluate the criteria for the thyroid function. ‘Normal’ ranges for various thyroid parameters were thus estimated. Two-dimensional statistical methods, including the application of bivariate tolerance areas (ellipses), were employed to test the diagnostic consequences of correlated variations between early and late radioiodine uptakes and between the fractions of plasma radioactivity. Labelled iodine in urine and iodide in plasma were dependent on age and kidney function.

Key Words:

• Bivariate tolerance ellipses
• fractions of plasma radioiodine
• iodine metabolism
• normal ranges
• radioiodine test
• thyroid function