A Physician Asks Your Laboratory to Begin Performing Thyroid-Stimulating Hormone

A physician asks your laboratory to begin performing thyroid-stimulating hormone (TSH) analyses on all specimens that have a free thyroxine (FT₄) analysis ordered,a practice that your laboratory currently does not perform.Your laboratory typically performs TSH only on those FT₄ specimens that are outside the population-based reference interval.The physician suggests using subject-based reference intervals,claiming that population-based intervals are clinically insensitive.What is the basis of this claim?

A) Subject-based reference values more closely resemble the group of reference individuals that were used to establish population-based reference intervals.
B) Standardized laboratory methods produce more accurate results when examining individual subject values.
C) Subject-based reference values are more easily tracked and applied in settings in which large numbers of specimens are analyzed.
D) Changes in a subject-based reference value might indicate altered biochemical status yet still be within the population-based healthy reference interval.