The thyroid gland produces the hormones L-thyroxine (T4) and L-triiodothyronine (T3), which regulate metabolic body processes, cellular respiration, total energy expenditure, growth and maturation ...

abbreviated THBR and include an indication of which hormone is used, i.e. THBR (T4) or THBR (T3). A T4 signal is preferred over T3 for THBR measurements, to better reflect T4 binding protein ...